Multi-market for Total Fertility Rate in each country in 2050 among HS grad women (x25)
Prediction market on manifold. Each market should be the name of a country. Resolves PROB to TFR * 25. If the named country doesn't exist in 2050, it resolves N/A and the successor country resolves PROB. Replacement = 2.1 TFR = 52.5% Only women with at least the equivalent of a high school diploma are counted, so countries can't goodhart this by importing a religious fundamentalist underclass I started by listing the top 25 countries by total GDP (PPP), but anyone can add addititional countries. [edit: if a country has no stats breaking down TFR by educational attainment, it resolves N/A]
Liquidity: $665. Resolves: 1/1/2051.