PostgreSQL contributor Tomas Vondra has published a blog post looking at development activity in the project, with data from the late 1990s to today. We're doing ~50 commits per week, give or take. In ~2010 we were doing maybe 25/week, and the trend seems to be a slow and consistent growth. The monthly average makes the trend a bit easier to spot. Which is good, although there's a lot of other important details (size of commits, are they new features or fixes, ...). It however nicely aligns with the number of active committers, which also grew ~2x between 2010 and today. So maybe that's working as expected.