(Note that the GiveWell and Open Philanthropy didn't formally split until 2017. GiveWell records $70.4m from Open Philanthropy in 2015, which isn't included in Open Philanthropy's own records. I've emailed them for clarification, but in the meantime, the overall story in the same: A rapid rise followed by several years of stagnation. Edit: I got a reply explaining that years are sometimes off by 1, see .)
If this data isn't surprising to you, it should be.
Several EA organizations work on actively growing the community, have been funding community growth for years and view it as an active priority:
80,000 Hours: The Problem Profiles page lists "Building effective altruism" as a "highest-priority area", right up there with AI and existential risk.
Open Philanthropy: Effective Altruism is one of their Focus Areas. They write "We're interested in supporting organizations that seek to introduce people to the idea of doing as much good as possible, provide them with guidance in doing so, connect them with each other, and generally grow and empower the effective altruism community."
EA Funds: One of the four funds is dedicated to Effective Altruism Infrastructure. Part of its mission reads: "Directly increase the number of people who are exposed to principles of effective altruism, or develop, refine or present such principles"
So if EA community growth is stagnating despite these efforts, it should strike you as very odd, or even somewhat troubling. Open Philanthropy decided to start funding EA community growth in 2015/2016 . It's not as if this is only a very recent effort.
As long as money continues to pour into the space, we ought to understand precisely why growth has stalled so far. The question is threefold:
Why was growth initially strong?
Why did it stagnate around 2015-2017?
Why has the money spent on growth since then failed to make a difference?
Here are some possible explanations.
Effective Altruism makes large moral demands, and frames things in a detached quantitative manner. Utilitarianism is already alienating, and EA is only more so.
This is an okay explanation, but it doesn't explain why growth initially started strong, and then tapered off.
2. Decline is the Baseline
Perhaps EA would have otherwise declined, and it is only thanks to the funding that it has even succeeded in remaining flat.
I'm not sure how to disambiguate between these cases, but it might be worth spending more time on. If the goal is merely community maintenance, different projects may be appropriate.
Around 2013, many core members of the community stopped posting on Less Wrong, because of both increased growth of the Bay Area physical community and increased demands and opportunities from other projects. MIRI's support base grew to the point where Eliezer could focus on AI research instead of community-building, Center for Applied Rationality worked on development of new rationality techniques and rationality education mostly offline, and prominent writers left to their own blogs where they could develop their own voice without asking if it was within the bounds of Less Wrong.
Specifically, some [LW · GW] blame the decline on SlateStarCodex:
With the rise of Slate Star Codex, the incentive for new users to post content on Lesswrong went down. Posting at Slate Star Codex is not open, so potentially great bloggers are not incentivized to come up with their ideas, but only to comment on the ones there.
In other words, SlateStarCodex and LessWrong catered to similar audiences, and SlateStarCodex won out. 
The recent data is distorted by the NYT incident, but basically the story is the same. Rapid rise to prominence in 2015, followed by a long plateau. So maybe some users left for Slate Star Codex in 2015, but that doesn't explain why neither community saw much growth from 2015 - 2020.
And here's the same chart, omitting the last 12 months of NYT-induced frenzy:
4. Community Stagnation was Caused by Funding Stagnation
One possibility is that there was not a strange hidden cause behind widespread stagnation. It's just that funding slowed down, and so everything else slowed down with it. I'm not sure what the precise mechanism is, but this seems plausible.
Of course, now the question becomes: why did Open Philanthropy giving slow? This isn't as mysterious since it's not an organic process: almost all the money comes from Good Ventures which is the vehicle for Dustin Moskovitz's giving.
Did Dustin find another pet cause to pursue instead? It seems unlikely. In 2019, they provided $274 million total, nearly all of which ($245 million) went to Open Philanthropy recommendations.
So is the entire stagnation hypothesis disproved? I don't think so. Google Trends tracks active interest, whereas Giving What We Can tracks cumulative interest. So a stagnant rate of active interest is compatible with increasing cumulative totals. Computing the annual growth rate for Giving What We Can, we see that it also peaks in 2015, and has been in decline ever since:
To sum up:
Alienation is not a good explanation, this has always been a factor
EA may have declined more if not for the funding
SlateStarCodex may have taken some attention, but it also hasn't grown much since 2015
Funding stagnation may cause community stagnation; the causal mechanism is unclear
Giving What We Can membership has grown, but it measures cumulative rather than active interest. Their rate of growth has declined since 2015.
A Speculative Alternative: Effective Altruism is Innate
You occasionally hear stories about people discovering LessWrong or "converting" to Effective Altruism, so it's natural to think that with more investment we could grow faster. But maybe that's all wrong.
My favored means of procrastination has often been lurking on discussion forums. I can't get enough of that stuff ...Reading forums gradually became a kind of disaster tourism for me. The same stories played out again and again, arguers butting heads with only a vague idea about what the other was saying but tragically unable to understand this.
....While surfing Reddit, minding my own business, I came upon a link to Slate Star Codex. Before long, this led me to LessWrong. It turned out I was far from alone in wanting to understand everything in the world, form a coherent philosophy that successfully integrates results from the sciences, arts and humanities, and understand the psychological mechanisms that underlie the way we think, argue and disagree.
It's not that John discovered LessWrong and "became" a rationalist. It's more like he always has this underlying compulsion, and then eventually found a community where it could be shared and used productively.
In this model, Effective Altruism initially grows quickly as proto-EAs discover the community, then hits a wall as it saturates the relevant population. By 2015, everyone who might be interested in Effective Altruism has already heard about it, and there's not much more room for growth no matter how hard you push.
One last piece of anecdotal evidence: Despite repeated attempts, I have never been able to "convert" anyone to effective altruism. Not even close. I've gotten friends to agree with me on every subpoint, but still fail to sell them on the concept as a whole. These are precisely the kinds of nerdy and compassionate people you might expect to be interested, but they just aren't. 
In comparison, I remember my own experience taking to effective altruism the way a fish takes to water. When I first read Peter Singer, I thought "yes, obviously we should save the drowning child." When I heard about existential risk, I thought "yes, obvious we should be concerned about the far future". This didn't take slogging through hours of blog posts or books, it just made sense. 
Some people don't seem to have that reaction at all, and I don't think it's a failure of empathy or cognitive ability. Somehow it just doesn't take.
While there does seem to be something missing, I can't express what it is. When I say "innate", I don't mean it's true from birth. It could be the result of a specific formative moment, or an eclectic series of life experiences. Or some combination of all of the above.
Fortunately, we can at least start to figure this out through recollection and introspection. If you consider yourself an effective altruist, a rationalist or anything adjacent, please email me about your own experience. Did Yudkowsky convert you? Was reading LessWrong a grand revelation? Was the real rationalism deep inside of you all along? I want to know.
I'm at email@example.com, or if you read the newsletter, you can reply to the email directly. I might quote some of these publicly, but am happy to omit yours or share it anonymously if you ask.
Data for Open Philanthropy and Good Ventures is available here. Data for Giving What We Can is here. If you know how Open Philanthropy's grant database accounts for funding before it formally split off from GiveWell in 2017, please let me know.
Disclosure: I applied for funding from the EA Infrastructure Fund last week for an unrelated project.
 Open Philanthropy writes:
Hi, thanks for reaching out.
Our database's date field denotes a given grant's "award date," which we define as the date when payment was distributed (or, in the case of grants paid out over multiple years, when the first payment was distributed). Particularly in the case of grants to organizations based overseas, there can be a short delay between when a grant is recommended/approved and when it is paid/awarded. (For more detail on this process, including average payment timelines, see our Grantmaking Stages page.) In 2015/2016, these payment delays resulted in top charity grants to AMF, DtWI, SCI, and GiveDirectly totaling ~$44M being paid in January 2016 and falling under 2016 in your analysis even as GiveWell presumably counted those grants in its 2015 "money moved" analysis.
Payment delays and "award date" effects also cause some artificial lumpiness in other years. For example, some of the largest top charity grants from the 2016 giving season were paid in January 2017 (SCI, AMF, DtWI) but many of the largest 2017 giving season grants were paid in December 2017 (Malaria Consortium, No Lean Season, DtWI). This has the effect of artificially inflating apparent 2017 giving relative to 2018. Other multi-year grants are counted as awarded entirely in the month/year the first payment was made -- for example, our CSET grant covering 2019-2023 first paid in January 2019. So I wouldn't read too much into individual year-to-year variation without more investigation.
Hope this helps.
 For more on OpenPhil's stance on EA growth, see this note from their 2015 progress report:
Effective altruism. There is a strong possibility that we will make grants aimed at helping grow the effective altruist community in 2016. Nick Beckstead, who has strong connections and context in this community, would lead this work. This would be a change from our previous position on effective altruism funding [EA · GW], and a future post will lay out what has changed. [emphasis mine]
 My Giving What We Can dataset also has a column for money actually donated, though the data only goes back to 2015.
 I'm conflating effective altruism with rationalism in this section, but I don't think it matters for the sake of this argument.
 For what it's worth, I'm typically pretty good at convincing people to do things outside of effective altruism. In every other domain of life, I've been fairly successful at getting friends to join clubs, attend events, and so on, even when it's not something they were initially interested in. I'm not claiming to be exceptionally good, but I'm definitely not exceptionally bad.
But maybe this shouldn't be too surprising. Effective Altruism makes a much larger demand than pretty much every other cause. Spending an afternoon at a protest is very different from giving 10% of your income.
Analogously, I know a lot of people who intellectually agree with veganism, but won't actually do it. And even that is (arguably) easier than what effective altruism demands.
Before reading A Human's Guide to Words [? · GW] and The Categories Were Made For Man, I went around thinking "oh god, no one is using language coherently, and I seem to be the only one seeing it, but I cannot even express my horror in a comprehensible way." This felt like a hellish combination of being trapped in an illusion, questioning my own sanity, and simultaneously being unable to scream. For years, I wondered if I was just uniquely broken, and living in a reality that no one else seemed to see or understand.
It's not like I was radicalized or converted. When I started reading Lesswrong, I didn't feel like I was learning anything new or changing my mind about anything really fundamental. It was more like "thank god someone else gets it."
When did I start thinking this way? I honestly have no idea. There were some formative moments, but as far back as I can remember, there was at least some sense that either I was crazy, or everyone else was.
Tldr: I agree the 'top of the funnel' seems to not be growing (i.e. how many people are reached each year). This was at least in part due to a deliberate shift in strategy. I think the 'bottom' of the funnel (e.g. money and people focused on EA) is still growing. Eventually we'll need to get the top of the funnel growing again, and people are starting to focus on this more.
Around 2015, DGB and The Most Good You Can Do were both launched, which both involved significant media attention that aimed to reach lots of people (e.g. two TED talks). 80k was also focused on reaching more people.
After that, the sense was that the greater bottleneck was taking all these newly interested people (and the money from Open Phil), and making sure that results in actually useful things happening, rather than reaching even more people.
(There was also some sense of wanting to shore up the intellectual foundations, and make sure EA is conveyed accurately, rather than as "earn to give for malaria nets", which seems vital for its long-term potential. There was also a shift towards niche outreach, rather than mass media - since mass media seems better for raising donations to global health, but less useful for something like reducing GCBRs, and although good at reaching lots of people, wasn't as effective as the niche stuff.)
E.g. in 2018, 80k switched to focusing on our key ideas page and podcast, which are more about making sure already interested people understand our ideas than reaching new people; Will focused on research and niche outreach, and is now writing a book on longtermism. GWWC was scaled down, and Toby wrote a book about existential risk.
This wasn't obviously a mistake since I think that if you track 'total money committed to EA' and 'total number of people willing to change career (or take other significant steps)', it's still growing reasonably (perhaps ~20% per year?), and these metrics are closer to what ultimately matter. (Unfortunately I don't have a good source for this claim and it relies on judgement calls, though Open Phil's resources have increased due to the increase in Dustin Moskovitz's net worth; several other donors have made a lot of money; the EA Forum is growing healthily; 80k is getting ~200 plan changes per year; the student groups keep recruiting people each year etc.)
One problem is that if the top of the funnel isn't growing, then eventually we'll 'use up' the pool of interested people who might become more dedicated, so it'll turn into a bottleneck at some point.
And all else equal, more top of funnel growth would be better, so it's a shame we haven't done more.
My impression is that people are starting to focus more on growing the top of the funnel again. However, I still think the focus is more on niche outreach, so you'd need to track a metric more like 'total number of engaged people' to evaluate it.
I weakly upvoted this for the second section, which is a discussion I've had with many people in person and is something I'm glad to see in writing. But I found the title offputting given the very modest amount of evidence presented in support of the claim.
There are a huge number of things you could check to gauge the total size of the EA movement. You chose GiveWell's total funding, Google Trends data, and the growth of Giving What We Can.
(These are all reasonable things to choose, but I don't think they are collectively decisive enough to merit a title as strongly-worded as "why hasn't effective altruism grown?" I'm really just objecting to the title here, rather than the spirit or execution of this project.)
The last number is solid evidence of weaknesses in community building strategy: CEA acknowledges that they should have put more staff time into Giving What We Can post-2016 And when Luke Freeman took over as the project's first full-time leader in years, GWWC saw faster growth (in absolute terms) than ever before. The rate of growth wasn't high compared to 2016, but it's encouraging that someone was able, within a few months, to break a record set by a larger team working full-time on GWWC when there was (presumably) more low-hanging fruit available to pick.
As for the other items:
When I look at GiveWell's funding to get evidence on EA growth, I mostly care about the dark blue number, which represents "money that didn't come from the same two people" (not sure whether Incubation Grants are Good Ventures or other funds off the top of my head). GiveWell gets a lot more donations from outside Good Ventures now than it did in 2018; I wouldn't be surprised to see it more than double the 2015 figure in 2021.
On Google Trends: You identify yourself that these numbers can be a bit messy, but I agree with you that they seem like at least weak evidence that public interest in the specific term "effective altruism" hasn't grown. However, I don't think any of the orgs you quoted as aiming to grow the community were trying to achieve that kind of growth — there's been much more focus on developing specific, smaller-scale pipelines for directing money and talent to EA projects.
Some examples of things that I believe have been growing, with numbers where I can easily find them:
Academic publications on EA-related topics (e.g. 310 Google Scholar results for "existential risk" in 2015, 1020 in 2020; 25 vs. 47 for "wild animal suffering")
Number of students participating in EA "fellowship" programs (doing a lot of structured reading and activities)
Number of active EA groups worldwide (EA Hub currently lists 230; I don't know the figure from 2015, but I did start an EA group in 2014 and remember being able to find maybe a few dozen groups total when I looked at places like THINK [that year's equivalent of EA Hub]).
EA Forum activity (pageviews roughly doubled from 2019 to 2020)
Number of EA community members involved in government/public policy in some capacity (people in this category don't always announce their views publicly, so I don't think good figures will be available anywhere — this claim is anecdotal, based on many stories I've heard about people starting this work and the creation of groups like APPGFG and organizations like CSET)
Number of people employed by EA-aligned organizations (again, no hard numbers, but a lot of charities have started up within the last few years, and I'd be surprised if a similar number had shut down)
I wish I had more data easily to hand on some of these figures, but I'd bet at 10:1 on any one of them being higher in 2020 than 2015. And while none of them are slam-dunk evidence that EA is definitely "growing" by any reasonable definition of the word, I think they collectively paint a clear picture.
I fear that most of these metrics aren't measures of EA growth, so much as of reaping the rewards of earlier years' growth. They seem compatible with a picture where EA grew a lot until 2015 and then these EAs slowly became more engaged, moved into different roles and produced different outcomes, without EA engaging significantly more new people since 2015.
We have some concrete insight about the 'lag' between people joining EA and different outcomes based on EA Survey data:
- On engagement, looking at years in EA and self-reported level of engagement, we can see that it appears to take some years for people to become highly engaged. Mean engagement continues to increase up until 5-6 years in EA, at which point it plateaus. (Although, of course, this is complicated by potential attrition, i.e. people who aren't engaged dropping out of earlier cohorts. We'll talk more about this in this year's series).
- The mean length of time between someone first hearing about EA and taking the GWWC pledge (according to 2019 EAS data) is 1.16 years (median 1 year). There are disproportionately more new EAs in the sample though, since (germane to this discussion!) EA does seem to have consistently been growing year on year (although per the above this could also be confounded somewhat by attrition) and of course people who just heard of EA in the last year couldn't have taken the GWWC pledge more than 1 year after they first heard of EA. So it may be that a more typical length of time to take the pledge is a little longer.
- Donations: these arguably have a lower barrier to entry compared to other forms of engagement, yet still increase dramatically with more time in EA.
Of course, this is likely somewhat confounded by the fact that people who have spent more time in EA have also spent more time developing their career and so their ability to donate, but the same confound could account for observed increase in EA outputs over time even if EA weren't growing.
This seems like it could be true for some of the figures, but not all. I'd strongly expect "number of active EA groups" to correlate with "number of total people engaged in EA". The existence of so many groups may come from people who joined in 2015 and started groups later, but many group leaders are university students, so that can't be the whole story.
In this case, do you think it's likely that there are about as many group members as before, spread across more groups? Or maybe there are more group members, but the same number of total people engaged in EA, with a higher % of people in groups than before?
I think this applies to growth in local groups particularly well. As I argued in this comment [EA(p) · GW(p)] above, local groups seem like a particularly laggy metric due to people usually starting local groups after at least a couple of years in EA. While I've no doubt that many of the groups that have been founded by people who joined since 2015*, I suspect that even if we cut those people out of the data, we'd still see an increase in the number of local groups over that time frame- so we can't infer that EA is continuing to grow based on increase in local group numbers.
*Indeed, we should expect this because most people currently in the EA community (at least as measured by the EA Survey) are people who joined since 2015. In each EA survey, the most recent cohorts are almost always much larger than earlier cohorts (with the exception of the most recent cohort of each survey since these are run before some EAs from that year will have had a chance to join). See this graph which I previously shared [EA(p) · GW(p)], from 2019 data, for example:
(Of course, this offers, at best, an upper bound on growth in the EA movement, since earlier cohorts will likely have had more attrition).
do you think it's likely that there are about as many group members as before, spread across more groups? Or maybe there are more group members, but the same number of total people engaged in EA, with a higher % of people in groups than before?
There's definitely been a very dramatic increase in the percentage of EAs who are involved in local groups (at least within the EA Survey sample) since 2015 (the earliest year we have data for).
In EAS 2019 this was even higher (~43%) and in EAS 2020 it was higher still (almost 50%).
So higher numbers of local group members could be explained by increasing levels of engagement (group membership) among existing EAs. (One might worry, of course, that the increase in percentage is due to selective attrition, but the absolute numbers are higher than 2015 as well.)
Unfortunately we don't have good data on the number of local group members, because the measures in the Groups Survey were changed between 2019-2020. On the one measure which I was able to keep the same (total number of people engaged by groups) there was a large decline 2019-2020, but this is probably pandemic-related.
University group members are mostly undergraduates, meaning they are younger than ~22. This implies that they would have been younger than 18 in 2017, and there was almost no one [EA(p) · GW(p)]like that on the 2017 survey. And they would have been under 16 in 2015, although I don't think we have data going back that far. I can think of one or two people who might have gotten involved as 15-year-olds in 2015, but it seems quite rare. Is there something I'm missing?
I'm not sure where you are disagreeing, because I agree that many people founding groups since 2015 will in fact have joined the movement later than 2015. Indeed, as I show in the first graph in the comment you're replying to, newer cohorts of EA are much larger than previous cohorts, and as a result most people (>60%) in the movement (or at least the EA Survey sample[^1]) by 2019 are people who joined post-2015. Fwiw, this seems like more direct evidence of growth in EA since 2015 than any of the other metrics (although concern about attrition mean that it's not straightforward evidence that the total size of the movement has been growing, merely that we've been recruiting many additional people since 2015).
My objection is that pointing to the continued growth in number of EA groups isn't good evidence of continued growth in the movement since 2015 due to lagginess (groups being founded by people who joined the movement in years previous). It sounds like your objection is that since we also know that some of the groups are university groups (albeit a slight minority) and university groups are probably mostly founded by undergraduates, we know that at least some of the groups founded since 2015 were likely founded by people who got into EA after 2015. I agree this is true, but think we still shouldn't point to the growth in number of new groups as a sign of growth in the movement because it's a noisy proxy for growth in EA, picking up a lot of growth from previous years. (If we move to pointing to separate evidence that some of the people who founded EA groups probably got into EA only post 2015, then we may as well just point to the direct evidence that the majority of EAs got into EA post-2015!)
[^1]: I don't take this caveat to undermine the point very much because, if anything I would expect the EA Survey sample to under-represent newer, less engaged EAs and over-represent EAs who have been involved longer.
I think maybe I was confused about what you are saying. You said:
I think this applies to growth in local groups particularly well... While I've no doubt that many of the groups that have been founded by people who joined since 2015*, I suspect that even if we cut those people out of the data, we'd still see an increase in the number of local groups over that time frame- so we can't infer that EA is continuing to grow based on increase in local group numbers.
But then also:
Fwiw, this seems like more direct evidence of growth in EA since 2015 than any of the other metrics
In my mind, A being evidence of B means that you can (at least partially) infer B from A. But I'm guessing you mean "infer" to be something like "prove", and I agree the evidence isn't that strong.
DM: While I've no doubt that many of the groups that have been founded by people who joined since 2015*, I suspect that even if we cut those people out of the data, we'd still see an increase in the number of local groups over that time frame- so we can't infer that EA is continuing to grow based on increase in local group numbers.
BW: It sounds like maybe when you say "we can't infer that EA is continuing to grow based on increase in local group numbers" you mean "part of the growth might be explained by things other than what would be measured by a change in number of groups"? (Or possibly "increasing group numbers is evidence of growth since 2015, but not necessarily evidence of growth since, say, 2019"?)
I meant something closer to: 'we can't infer Y from X, because we'd still expect to observe X even if ¬Y.'
My impression is still that we have been somewhat talking past each other, in the way I described in the second paragraph of my previous comment. My core claim is that we should not look at the number of new EA groups as a proxy for growth in EA, since many new groups will just be a delayed result of earlier growth in EA, (as it happens I agree that EA has grown since 2015, but we'd see many new EA groups even if it hadn't). Whereas, if I understand it, your claim seems to be that as we know that at least some of the new groups were founded by new people to EA, we know that there has been some new EA growth.
Thanks for this post. One dataset not included in this analysis though is the number of EA groups. CEA's 2019 local EA group organizers survey data shows that EA has grown in terms of number of active groups significantly since 2015, but the number of new groups founded per year was pretty stagnant from 2015 to 2018. The screenshots below are taken from the survey report.
However, according to CEA's 2020 annual review, they tracked 250 active groups via the EA Groups survey, compared to 176 at the end of 2019. So I think EA, in terms of number of active groups, has actually grown a lot in 2020 compared to 2015-2019.
It would be great if CEA released a writeup on the data from the EA Groups 2020 Survey so we can have updated numbers for the two figures above.
Just to clarify, the EA Groups Survey is a joint project of Rethink Priorities and CEA (with all analysis done by Rethink Priorities). The post you link to is written by Rethink Priorities staff member Neil Dullaghan [EA · GW].
The writeup for the 2020 survey should be out within a month.
according to CEA's 2020 annual review, they tracked 250 active groups via the EA Groups survey, compared to 176 at the end of 2019. So I think EA, in terms of number of active groups, has actually grown a lot in 2020 compared to 2015-2019.
This isn't a safe inference, since it's just comparing the size of the survey sample, and not necessarily the number of groups. That said, we do observe a similar pattern of growth in 2020 as in 2019.
Ah yes, thanks for clarifying and sorry for the omission! Looking forward to that writeup. Will there be an estimate of the number of groups including outside of the survey sample for that writeup David?
An "estimate of the number of groups including outside of the survey sample" wouldn't quite make sense here, because I think we have good grounds to think that we (including CEA) know of the overwhelming majority of groups that exist(ed in 2020) and know that we captured >90% of the groups that exist.
For earlier years it's a bit more speculative, what we can do there is something like what I mentioned in my reply to habryka comparing numbers across cohorts across year to get a sense of whether numbers actually seem to be growing or whether people from the 2019 survey are just dropping out.
Thse graphs are surprising to me. They seem to assume that no groups were dying in these years? I mean, that's plausible since they are all pretty young, but it does seem pretty normal for groups to die a few years after being founded.
I think the first graph only counts the number of active local groups. It is true and pretty normal that some groups become inactive after a few years of being founded. And I think the second graph only covers active groups by the year they were founded, but I could be wrong.
Yeh these graphs are purely based on groups who were still active and took the survey in 2019, so they won't include groups that existed in years pre-2019 and then stopped existing before 2019. We've changed the title of the graph to make this clearer.
That said, when we compare the pattern of growth across cohorts across surveys for the LGS, we see very similar patterns across years with closely overlapping lines. This is in contrast to the EA Surveys where we see consistently lower numbers within previous cohort across successive surveys, in line with attrition. This still wouldn't capture groups which come into existence and then almost immediately go out of existence before they have chance to take a survey. But I think it suggests the pattern of strong growth up to and including 2015 and then plateau (of growth, not of numbers) is right.
One other thing to bear in mind about growth in groups is that, as I discussed in my reply to Aaron [EA(p) · GW(p)], this metric may be measuring the fruits of earlier growth more than current growth in the movement. My impression that many groups are founded by people who are not themselves new to EA, so if you get people into the movement in year X, you would expect to see groups being founded some years after they join. This lag may give the false reassurance than the movement is still growing when really it's just coasting on past successes.
Scattered thoughts on this, pointing in various directions.
TL;DR: Measuring and interpreting movement growth is complicated.
Things I'm relatively confident about:
You need to be careful about whether the thing you are looking at is a proxy for 'size of EA' or a proxy for a derivative, i.e. 'how fast is EA growing'. I think Google Trends searches for 'Effective Altruism' are mostly the latter; it's something people might do on the way into the movement, but not something I would ever do.
After correcting for (1), my rough impression is that EA grew super-linearly up to about 2016, and then approximately linearly after that up to about March 2020. Intepretation of many metrics since COVID is complicated by, well, COVID. One salient-to-me way to think about linear growth is that each year some fraction of the new crop of university students discover EA and some fraction of them take to it.
Givewell money moved is obviously going to be impacted by a shift away from global poverty/health as a focus area within the movement. We have survey data [EA · GW] which suggests this has happened over the time period in question. In that context, a 93% increase in non-Open-Phil money moved to the shrinking cause area between 2015 and 2019 is pretty good.
OTOH, when looking at any kind of money moved over time you need to remember that EA's non-Open-Phil financial power should increase regardless of the number of people increasing. The movement is young and full of the types of people who have had large income increases between 2015 and 2020. For example, while I couldn't find the data quickly, I believe >>50% of GWWC members were students in 2015 and <50% are now.
Also on that hand, I expect most of Givewell's donors don't self-identify as EAs. Whether this matters is unclear, makes it a bit of a weak proxy though.
I reallydon't think it makes sense to treat Alienation/Demandingness as a constant. Scott's response to this matches my impressions, and one of the things it flags is how the level of demands on proto-EAs have increased, in my opinion by a lot. I think this is true in both the 'level of dedication required' sense and the 'level/specificity of skills required' sense.
This is particularly salient, perhaps too salient, to me for personal reasons. I am a top-third Maths graduate from a top university who has donated roughly half of my income to date, but I don't quite hit the type and level of dedication/skill that I perceive is desired, and partly as a result I doubt I would have gotten involved in the movement if I had been born 6 years later. I want to be explicit that this isn't necessarily a problem - that judgement is very sensitive to beliefs about relative values of different types of individuals - I'm just providing a personal anecdote that if it generalises would serve as partial explanation for the tailing off of growth rates.
Things I am less confident about:
While the level of demands has increased, I think EA's online spaces are actually less supportive than they used to be, creating a gap that can easily leave people disillusioned, especially if they are geographically distant from major movement hubs. Many in-person spaces seem to be healthier, but are always going to grow less rapidly.
The other gap leaving people disillusioned is the lack of actual things to do [EA · GW], especially at 'entry levels' of dedication but also at higher levels if you strike out on job applications. I chuckle sadly every time I read this piece [EA · GW], in particular the paragraph quoted below.
I do actually agree a lot of people who get seriously involved (say >20% dedication, including anyone who has changed their career path for EA reasons) in EA seem to have liked it as soon as they hear about it. But:
I think this is at best a partial account of why growth has stalled, because as of now my impression is that essentially nobody (<10% of university students) has heard about it.
If you lower the dedication bar at all I get a lot more positive on the possibility of convincing people. Partly this is for personal reasons, my closest friend from university has taken the GWWC pledge and I'm >50% confident he would not have done so if it weren't for me talking about EA. I just don't expect him to 'go beyond' that pledge or otherwise engage with the community.
If I do check my own path, I was introduced to EA or Rationality at least three times before something stuck: I saw Toby Ord give an interview, was nudged into reading parts of the Sequences by my first job, then a university friend pointed me to HPMOR, then finally a different university friend interned at GWWC. So on the one hand it does seem with hindsight like these communities kept knocking on my door, but on the other I didn't actually do anything with the first few points of contact. For me it was when I was asked to do something concrete, achievable and valuable that I switched my attention. I know others' mileage varies a lot here; some people are particularly drawn to the intellectual aspect for example. But it means that even 'innate' EAs might need exposure to the representation of EA that matches what they are looking for.
Finally, there are at least two candidate explanations of 'many people who are seriously involved with EA liked it as soon as they heard about it', if true. EA could be innate, or we could suck at providing the incentive gradients/incremental support necessary to turn less-committed people into more-committed people. Both would create that pattern.
Hey you! You know, all these ideas that you had about making the world a better place, like working for Doctors without Borders? They probably aren’t that great. The long-term future is what matters. And that is not funding constrained, so earning to give is kind of off the table as well. But the good news is, we really, really need people working on these things. We are so talent constraint… (20 applications later) … Yeah, when we said that we need people, we meant capable people. Not you. You suck.
Interesting observations. I only have one thought that I don't see mentioned in the comments.
I see EA as something that is mostly useful when you are deciding how you want to do good. After you figured it out, there is little reason to continue engaging with it.  Under this model of EA, the fact that engagement with EA is not growing would only mean that the number of people who are deciding how to do good at any given time is not growing. But that is not what we want to maximize. We want to maximize the number of people actually working on doing good. I think that EA fields like AI safety and effective animal advocacy have been growing though I don't know. But I think this model of EA is only partially correct.
E.g., Once someone figures out that they want to be an animal advocate, or AI safety researcher, or whatever, there is little reason for them to engage with EA. E.g., I am an animal advocacy researcher and I would probably barely visit the EA forum if there was an effective animal advocacy forum (I wish there was). Possibly one exception is earning-to-give, because there is always new information that can help decide where to give most effectively, and EA community is a good place to discuss that. But even that has diminishing returns. Once you figured out your general strategy or cause, you may need to engage with EA less. ↩︎
I completely agree with this, thank you for writing it up! This is also an issue I have with some elements of the 'drifting' debate - I'm not too fussed whether someone stays involved in the EA community (though I think it can be good to check whether there have been new insights), I care about people actually still doing good.
This sentiment came up a fair amount in the [2019 EA Survey data](https://forum.effectivealtruism.org/posts/F6PavBeqTah9xu8e4/ea-survey-2019-series-community-information#Changes_in_level_of_interest_in_EA__Qualitative_Data) about reasons why people had decreased levels of interest in EA over the last 12 months.
It didn't appear in our coding scheme as a distinct category, but particularly within the "diminishing returns" category below, and also in response to the question about barriers to further involvement in the EA community below that, there were a decent number of comments expressing the view that they were interested in having impact and weren't interested in being involved in the EA community.
It's probably unnecessary but I tried to think of a metaphor that would help to visualize this as that helps me to understand things. Here is the best one I have. You want to maximize the number of people partying in your house. You observe that the number of people in the landing room is constant and conclude that the number of people partying is not growing. (Landing room in this metaphor is EA). But that is only because people are entering the landing room, and then going to party in different rooms (different rooms are different cause areas). So the fact that the number of people in the landing room is constant might mean that the party is growing at a constant rate. Or perhaps even the growth rate is increasing, but we also learnt how to get people out of the landing room into other rooms quicker which is good.
That's one way to see it, but I thought that ideally you're supposed to keep considering all the possible "interventions" you can personally do to help moral patients. That is, if the most effective cause that matches your skills (and is neglected, etc etc) changes, you're supposed to switch.
In practice that does not happen much, because skills and experience in one area are most useful in the same area, and because re-thinking your career constantly is tiring and even depressing; but it could be that way.
If it was that way, people who have decided on their cause area (for the next say, 5 years) should still call themselves EAs.
One last piece of anecdotal evidence: Despite repeated attempts, I have never been able to "convert" anyone to effective altruism. Not even close. I've gotten friends to agree with me on every subpoint, but still fail to sell them on the concept as a whole. These are precisely the kinds of nerdy and compassionate people you might expect to be interested, but they just aren't.
In comparison, I remember my own experience taking to effective altruism the way a fish takes to water.
I've had many conversations about EA, and I've convinced at least a few people about the basic "give more to charity, and find better charities" idea (people who didn't seem to have an underlying compulsion to give). And I've definitely heard stories of people who became gradually more convinced by arguments related to e.g. longtermism or wild animal suffering, despite initial reluctance or commitment to what they were previously working on.
What would you count as a "conversion"? Someone who is initially resistant to one or more EA-related ideas, but eventually changes their mind? For any definition, I think examples are out there, though how common they are will depend on which definition we use.
One place to look for examples would be EA-aligned orgs that hire people who aren't particularly EA-oriented. Staff at these orgs are immediately exposed to lots of EA philosophy, but (in some cases I've heard of) only gradually shift their views in that direction, or start off not caring much but become more interested as they see the ideas put into practice.
I can try to track down people who I think this would describe and connect them with you. But first — what are you planning to do with the emails you receive? Would it be better for people to describe their "conversion" experiences on a Forum thread?
Would it be better for people to describe their "conversion" experiences on a Forum thread?
I suspect the EA Survey is the ideal place to ask this sort of question because selection effects will be lowest that way. The best approach might be to gather some qualitative written responses, try to identify clusters in the responses or dimensions along which the responses vary, then formulate quantitative survey questions based on the clusters/dimensions identified.
As Katja's response alludes to, the non-Open-Phil chunk of GiveWell has more than doubled since 2015 (plus EA funds has gone from zero to $9M, etc.)
I see a few comments at the Reddit/LessWrong versions of this post intimating that EA does not want [much] more money, or has stopped trying to fundraise. This was not my impression at all. Is it not true that even just considering GiveWell's top charities and near-misses, they could absorb many millions more without being saturated?