Federal Housing Finance Agency

The national conforming loan limit for mortgages that finance single-family one-unit properties increased from $33,000 in the early 1970s to $417,000 for 2006-2008, with limits 50 percent higher for four statutorily-designated high cost areas: Alaska,  Hawaii, Guam, and the U.S. Virgin Islands.  Since 2008, various legislative acts increased the loan limits in certain high-cost areas in the United States.  While some of the legislative initiatives established temporary limits for loans originated in select time periods, a permanent formula was established under the Housing and Economic Recovery Act of 2008 (HERA).  The 2021 loan limits have been set under the HERA formula. 

These annual national indexes should be considered developmental. As with the standard FHFA HPIs, revisions to these indexes may reflect the impact of new data or technical adjustments. Indexes are calibrated using appraisal values and sales prices for mortgages bought or guaranteed by Fannie Mae and Freddie Mac. Index values always reflect data from that year. Three HPI values are provided and, since the indexes reflect cumulative appreciation since a certain period, the values reflect the base year being used (annual appreciations are the same). 

The HPI is a broad measure of the movement of single-family house prices. The HPI is a weighted, repeat-sales index, meaning that it measures average price changes in repeat sales or refinancing's on the same properties. This information is obtained by reviewing repeat mortgage transactions on single-family properties whose mortgages have been purchased or securitized by Fannie Mae or Freddie Mac since January 1975.