Source: Calculated Risk Blog — 

I’ve put together my own affordability index – since 1976 – that is similar to the FirstAm approach (more of a house price index adjusted by mortgage rates and the median household income).

I used median income from the Census Bureau (estimated 2021 and 2022), assumed a 15% down payment, and used a 2% estimate for property taxes, insurance and maintenance. This is probably low for high property tax states like New Jersey and Texas, and too high for lower property tax states. If we were including condos, we’d also include HOA fees too (this is excluded).