Hide table of contents

I think it might be interesting and valuable to create a "list of numbers every EA should know", in a similar vein to Latency Numbers Every Programmer Should Know and Key Numbers for Cell Biologists.

I was originally thinking of either a) making the whole list myself, or b) convincing someone else (eg, an RP intern) to do it, but on AaronGertler's advice I decided to turn to the Forum to help with crowdsourcing this problem. 

We can use upvotes/downvotes and comments to debate which numbers should be worth including/excluding. 

So what are some key numbers that (almost) every EA should know?

Feel free to answer with either important numbers that you think are cause-specific (eg, numbers of chickens currently alive in factory farms, Toby Ord's x-risk estimates, extreme poverty rates in 1950  vs 2018) or relatively cause agnostic (eg, $billions that Open Phil has, expected lifespan of social movements, number of atoms in the observable universe).

New Answer
New Comment

6 Answers sorted by

I like this idea. Here is some brainstorming output. Apologies for it being unedited/not sorted by categories:

  • Age of the universe
  • Age of the Earth
  • Age of homo sapiens
  • Timing of major transitions in evolution
  • Timing of invention of writing, agriculture, and the Industrial Revolution
  • Gross world product
  • Time for which Earth remains habitable absent big intervention
  • Number of working days in a year
  • Number of working hours in a year
  • Net present value of expected lifetime earnings of some reference class such as "graduate from roughly such-and-such uni and discipline"
  • Good Ventures's total assets
  • Net present value of expected total EA-aligned capital by cause area/worldview
  • Number of parameters, training wall clock time, compute requirements, etc. for GPT-3 and some other landmark AI models
  • World population, population of China, population of India, population of Europe/the US, etc. - and predictions for these
  • Some key numbers about the human brain, e.g. number of synapses, energy requirements, ... 
  • Expected number of lives saved by smallpox eradication
  • Volume of yearly Open Phil grants by cause area
  • Volume of donations moved by/to GiveWell and ACE top charities
  • Number of people working on certain cause areas such as AI safety, GCBR reduction, nuclear security, ...
  • The 'Kaldor facts'
  • The 'Great Decoupling' of labor productivity from jobs + wages in the US
  • Some key stats about the distribution of world income and how it has changed, e.g., Milanovic's "elephant graph" and follow-ups
  • Some key stats about, e.g., South Korean economic growth since 1950
  • Something about speed of improvement in various technologies, e.g., Moore's Law, how quickly the price of solar panels or various chemicals has fallen, etc. - weighted toward things that seem more 'relevant', e.g., falling price of various biotech services
  • Number of wild animals (by appropriate groups, e.g., mammals, birds, invertebrates)
  • Number of bacteria
  • Number of atoms in the observable universe
  • USG budget
  • Chinese govt budget
  • Big tech market capitalization
  • Total budget of some key international institutions, e.g., UN, WHO, BWC, OPCW
  • World energy use
  • Certain physics-based limits to growth, and when we'd reach them on a business-as-usual trajectory
  • How much total compute there is, and how it's distributed (e.g. supercomputers vs. gaming consoles vs. personal computers vs. ...)
  • How much EAs should discount future financial resources
  • Size of the EA community
  • Number of impact-weighted career plan changes caused by 80k every year
  • Some key stats about impact distributions where we have them, e.g., on how heavy-tailed the DCP2 global health cost-effectiveness numbers are
  • How much does it cost to cause the equivalent of one life saved by donating to the top-rated GiveWell charity?
  • What 'trade ratio' between doubling someone's consumption and averting the death of a <5 year old do you need to have such that GiveDirectly becomes as cost-effective as AMF according to GiveWell's cost-effectiveness model?
  • How many years of, e.g., chicken suffering do you avert with marginal donations to, e.g., ACE top charities?
  • How many years of, e.g., chicken suffering do you avert by going vegan?
  • How many people, and what share of the world or regional population were killed in certain historical catastrophes such as the Black Death, the Mongol conquests, the Great Leap Forward, or the transatlantic slave trade?

FINAL UPDATE: The deck is now published.

This is amazing. I'd be happy to create an Anki deck for these and any other numbers suggested in this thread.

EDIT: Judging from the upvotes, there seems to be considerable interest in this. I will wait a few days until people stop posting answers and will then begin creating the deck. I'll probably use the CrowdAnki extension to allow for collaboration and updating; see the ultimate-geography GitHub repository for an example.

You can embed flashcard decks into LW and EA Forum posts: 


So you could consider creating one of those.

Wow, I didn't know about this feature.
JP Addison
I will absolutely study that deck.
Max Görlitz
I would also definitely use it, just one suggestion: It would be cool if you include a field with the source link for the number so it is easy to go back and take a look. I know it will be quite some work so thanks a ton! 
Hi, yes, we will have a 'source' field. I say 'we' because I'm doing this in collaboration with a user who kindly volunteered to help. I think we should be done by the end of the week.
Neel Nanda
I'd love to use such an Anki deck!
Alfredo Parra 🔸
I'd also use such a deck. Thanks for the offer! :)
Nick Zervoudis
I'd love to use this Anki deck too! Would it make sense to add a google form or some other way to let people express an interest in this, for when you've made it? (and/or to express interest in contributing)
I was thinking of announcing it in a separate post, given how much interest this has attracted.
I think that'd be great. I suspect you or somebody else ought to have a strong editorial line, because otherwise we'd have too many flashcards + it'd look too much like design by committee. 
Thanks so much! I'd also use that deck. 
Luke Freeman 🔸
I'd also love this – it's been on my todo list for about 5 years 😅
Made a save all based on the Anki deck, thank you! Probably janky/includes errors but had to start somewhere.

We've now turned most of these into Anki cards, but I'd appreciate pointers to reliable sources or estimates for the following:

  • Net present value of expected total EA-aligned capital by cause area/worldview
  • Number of people working on certain cause areas such as AI safety, GCBR reduction, nuclear security, ...
  • How much total compute there is, and how it's distributed (e.g. supercomputers vs. gaming consoles vs. personal computers vs. ...)
  • How much EAs should discount future financial resources
  • Size of the EA community

For others, I have the relevant information ... (read more)

I'm afraid I don't know of great sources for the numbers you list. They may also only exist for the distribution of compute. Perhaps the numbers on the EA community are too uncertain and dynamic to be a good fit for Anki anyway. On the other hand, it may be mainly the order of magnitude that is interesting, and it should be possible to get this right using crude proxies. One proxy for the size of the EA community could be the number of EA survey respondents (or perhaps one above a certain engagement level).  On the other points: * For the Great Decoupling you could use "total growth of US labor productivity since 1980" together with "total growth of median household income since 1980" (or both up to some recent year for which data is available). And the same for labor productivity vs. number of jobs since 2000. See, for instance, the graph here. You could also use the graph itself as an answer. * For changes in the distribution of world income, you could just use the two graphs in this article as answers (the 'elephant graph' is the one for 1988-2008, and there is also a newer one for 2008-2013/14). You could also extract some key numbers from these graphs, or some other statistics. E.g., the article provides the change of the Gini coefficient of the world income distribution, but this may have the downside that it's hard to interpret:  * For the heavy-tailedness of various distributions I'd use the share of, e.g., the top 10% and 1% in the total.
Thanks! It hadn't occurred to me to use the graph as the figure, but that's a good idea. On reflection, we could perhaps use "image occlusion" for this or other questions.
Amazing, thank you so much!

Numbers about the EA community seem useful for people to know if they have any interest in community building. Examples might include:

  • Monthly visitors to effectivealtruism.org
  • Monthly visitors to the EA Forum
  • Number of Giving What We Can members (though the "number of active members" is a different thing and hard to figure out, so not sure how useful this one is)
  • Number of active EA groups + their total membership
  • Number of people employed by all "EA-aligned" organizations combined
  • Annual donations to GiveWell, EA Funds, and maybe ACE/Founders Pledge
  • Annual grantmaking done by Open Phil

(Not listing numbers out of laziness + the hope that someone will create a non-Forum version of this, and get up-to-date numbers at that point.)

These can all be rough estimates, but if someone was off about one of these things by an order of magnitude, I'd think they had some poor models about some aspect of the EA community.

Other random numbers I'll suggest (again, rough estimate):

  • Number of people working in different fields (e.g. AI safety or wild animal suffering), and/or the annual funding available to people in those fields
  • Cost to avert a death by supporting a top GiveWell charity
  • Cost to get a chicken out of a cage for one year

I want to return to this post at some point, since I feel like my list should be longer. I hope others have better suggestions than mine!

Average yearly donation by EAs (EA survey respondents)

Maybe aggregate EA wealth (wealth held by EAs, or wealth intended for EA?), dominated by Open Phil and maybe a few other billionaires.

I really like this idea. Here are some obvious ones: 

  • Number of galaxys in the reachable lightcone: ~10^9 (this is conveniently pretty close to the total number of humans alive, so I sometimes like thinking that if we reach the stars, I might have ownership over ~1 galaxy) (Sourced from Eternity in Six Hours)
  • Number of stars in a galaxy: ~10^10 - 10^12 (also surprisingly close to the number of humans alive)
  • People alive: ~10^10
  • Chicken deaths in a year: ~10^10
  • U.S. Philanthropic donations per year: ~$10^11 - $10^12 ($450 billion in 2019)
  • U.S. Foundation donations per year: $10^11 ($77 billion a year
  • Chicken deaths in a year: ~10^10

I think that's about right in the US, ~50 billion worldwide, but ~20 billion alive at any moment worldwide.


OOps, yeah, good chance that I accidentally used a U.S. only source.

Given the donations / year figures, these seem relevant:

  • World Bank expenditures (inc. loans) per year: $10^11 ($61 billion)
  • UN expenditures per year: $10^11 ($48 billion)
  • EU expenditures per year: $10^12 ($182 billion)
  • ADB (Asian Development Bank) expenditures per year: $10^11 ($23 billion)

I think all figures were from around 2015, so these could now be different.

Some others are much smaller and therefore not included, such as GAVI, IMF, WHO, etc.

The last two should be 10^11 - 10^12 and 10^11, respectively?

Oops, that's why you don't try to do mental arithmetic that will shape the future of our lightcone at 1AM in the morning.

World population: ~7bn (India, China, Africa, Europe, the Americas, all have populations of ~1bn)

World GDP: ~$100trn (the EU, US, China all have GDPs of ~$20trn)

Median household income (worldwide, not in USA) is the thing that sticks with me the most and seems most eye-opening... Looking it up now, it seems that it is $15,900 per year. Imagine your entire household bringing in that much, and then think: that's what life would be like if we were right in the middle.

  • how many big power transitions ended in war
  • exponential growth numbers (e.g. rule of 72)
  • how many studies on average replicate in some important fields
  • roughly how much they value their own time
  • life expectancy range across all countries
  • average economic growth of the last decades of Europe, US, China, India
  • number of billionaires and millionaires in a few countries

exponential growth numbers (e.g. rule of 72)

My favorite exponential growth numbers:

1.01^20,000 = 10^86

1.03^7000 = 10^89

1.05^4000 = 10^84

If the economy were to grow by 1% annually for a mere 20,000 years (which is a blink of an eye on a geologic timescale), then the economy would grow by a factor of 10^86, which is more than the number of atoms in the observable universe.

Of course this won't happen, but when talking with people outside of EA about the question of how soon we might create AGI or how soon we might reach technological maturity or how soon we might create a civilization with more value in it each year than the value of all life that has ever lived on Earth so far, I sometimes find that peoples' intuition is that the answer to each question is a very long time, e.g. millions of years.

However, when I give these exponential growth numbers in this context it often acts as an intuition pump, such that whoever I'm talking to immediately sees that "millions of years" is too long, "thousands of years" is a lot more reasonable seeming than moments before, and "a few centuries or less" suddenly seems plausible.

Added most  of these, but would appreciate suggestions for the following:

  • how many big power transitions ended in war
  • roughly how much they value their own time
Cool, really looking forward to add them to my Anki!  Re: How many big power transitions ended in war I had the work from Graham Allison in mind here, not sure how set in stone it is but I had the impression it is a sufficiently solid rough estimate: Re: roughly how much they value their own time I would do a card where people are able to fill in their number, e.g. something like "Given my current schedule, to get me to do a task that I don't intrinsically value for one hour I'd need to by payed ___ €/$/..." And you might put Clearer Thinking's calculator as a link, so people can calculate it if they don't already know about this idea: https://programs.clearerthinking.org/what_is_your_time_really_worth_to_you.html
Sorted by Click to highlight new comments since:

I'm currently working on an article about QALYs per life saved (effectivealtruism.org), which would include measurements and a bunch of different values (e.g.  1 USD given to GWWC is [x] lives saved, [y] QALYs, etc). This might be relevant

More from Linch
Curated and popular this week
Relevant opportunities