GiveWell raised less than its 10th percentile forecast in 2023

Copying Chandler's response from the comments of the open thread:

Hi Arnold,

Thanks for your question! You are correct that our funds raised for metrics year 2023, $355 million, was below our 10% percentile estimate from our April 2023 blog post. We knew our forecasts were quite uncertain (80% confidence interval), and, looking back, we see two primary reasons that our forecasts were incorrect.

First, we were optimistic about the growth of non-Open Philanthropy funding. Our funds raised in 2023 from sources other than Open Philanthropy was $255 million, which is about at our 10% percentile estimate and is similar to the $253 million we raised in 2022 from sources other than Open Philanthropy (see the bottom chart in the blog post). We've continued to expand our outreach team, with a focus on retaining our existing donors and bringing in new donors, and we believe these investments will produce results over the longer term.

Second, Open Philanthropy committed $300 million in October 2023 and gave us flexibility to spend it over three years. We chose to allocate $100 million to 2023, 2024, and 2025, which is less than the $250 million we had forecast for 2023.

We discuss our current funding situation in a recent blog post about our approach to grant deployment timelines. We remain funding constrained at our current cost-effectiveness bar. Raising more money remains our single most important lever for maximizing impact---if we have more funding, we'll be able to make more grants to cost-effective programs that save and improve lives.

The other number I found potentially concerning was the 50% drop in year-over-year funds from new non-anon donors (p. 10 of the 2023 metrics report, see paste below). Funds from new/non-anon donors in 2021 were slightly higher than in 2022 per the 2022 metrics report, so the prior year wasn't the anomaly. 

I don't want to over-update on a single year's Y/Y difference, but my concern would grow if 2024 ended up similar to 2023.

I would not have predicted much effect of the FTX affair on GiveWell's new donor acquisition, but it's possible that played a role.

I wonder if this is mostly an effect of total effective giving growing less than GiveWell anticipated, or if more money is going to other effective giving opportunities.

Some evidence for the latter would be that in Europe different effective giving initiatives are growing (for example effektiv-spenden in Germany raised 13 million in 2022, and 19 million in 2023, doneer-effectief in the Netherlands raised 700.000 in 2022, and 2.5 million in 2023, I don't know if there is a similar trend in other EU-countries). I sense that within EA there is some shift in focus to causes such as animal wellbeing. Anecdotally I shifted my giving away from GiveWell towards the Doneer-Effectief animal wellbeing fund.  

However, these trends are not totally unexpected and in size might only explain a fraction of the 75 million difference between the median estimate and actual data of non-open philanthropy funding. Does anybody have a good sense of how effective giving as a whole changed between 2022 and 2023?