I was searching around trying to find data on long-term real estate prices and I came across a paper by Tom Nicholas and Anna Scherbina called, Real Estate Prices During the Roaring Twenties and the Great Depression.

Here are some stats about Manhattan real estate (from the paper) that you all might find interesting:

- In 1930, Manhattan housed 1.5% of the US population, but had approximately 4% of all US real estate wealth.

- To construct their price indices the authors randomly collected 30 real estate transactions per month in Manhattan between 1920 and 1939. The mean price per square foot in 1929 was $6.91 (year of Black Tuesday). And the mean price per square foot in 1939 – 10 years later – was $2.29.

- Buildings containing a store at grade tended to sell at higher prices. The authors speculate that this could be because a zoning change in 1916 made it difficult to open stores in “residential” areas.

- Buildings with three, four and five storeys tended to sell at a discount. Six storeys or higher and the buildings generally had an elevator, which resulted in higher pricing.