The Series Is Based On The Number Of 1-4 Family Mortgage Loans Outstanding And Includes Loans In Foreclosure. Source: Mortgage Bankers Association Of America, "National Delinquency Survey" This NBER data series q09084 appears on the NBER website in Chapter 9 at http://www.nber.org/databases/macrohistory/contents/chapter09.html. NBER Indicator: q09084