Source: Bureau Of The Census (See Introductory Notes On Bls-Dept. Of Commerce Data)
This NBER data series a02257 appears on the NBER website in Chapter 2 at http://www.nber.org/databases/macrohistory/contents/chapter02.html.
NBER Indicator: a02257
Release: NBER Macrohistory Database
National Bureau of Economic Research, Private Nonfarm New Housing Units, Constant Dollars for United States [A02257USA382NNBR], retrieved from FRED, Federal Reserve Bank of St. Louis https://research.stlouisfed.org/fred2/series/A02257USA382NNBR/, July 7, 2015.