Land in the U.S. accounts for 51.1% of the stock of non-financial assets.

“A key input into our analysis is the share of land and other non-produced assets in the overall value of physical assets, which in addition include produced physical assets, mainly man-made structures and capital goods. We approximate this figure for the US by subtracting the Bureau of Economic Analysis (BEA) measure of the stock of physical capital (defined as produced physical assets, including software and intellectual property) from the Fed Flow of Funds net worth of households and nonprofit organizations. By this measure, in the US land accounts for 51.1% of the stock of nonfinancial assets — and several percentage points more if we take into account the additional issues discussed in Section 7.1. This means that the tax base for US land taxation is very large.”

empirical