3 min read

December 2020 Case-Shiller Results & January Forecast: An Exclamation Point on 2020

Home prices as measured by the Case-Shiller indices continued to surge higher in December, setting the stage for more strong growth in the months ahead.

Written by Matthew Speakman on February 23, 2021

The S&P CoreLogic Case-Shiller U.S. National Home Price Index® rose 10.4% year-over-year in December (non-seasonally adjusted), up from 9.5% in November.
Annual growth was up from November in both the 20-city index (to 10.1%, from 9.2%) and 10-city index (to 9.8% from 8.9%).
Phoenix (+14.4%), Seattle (+13.6%), and San Diego (+13%) reported the highest year-over-year gains among markets in the 20-city index.

Adding an exclamation point to a year unlike any other, home prices continued their powerful surge higher in December, setting the stage for more strong growth in the months ahead.

The national Case-Shiller Home Price Index rose 10.4% year-over-year in December. The smaller 10- and 20-city composite indices almost matched that pace, at 9.8% and 10.1% year-over-year, respectively. The annual rate of growth was faster in December than in November in all three main indices. On a monthly (seasonally adjusted) basis, the national and 20-city indices were each up by 1.3%, while the 10-city index was up 1.2%.

	Zillow Forecast, Released 1/26/21	Actual Case-Shiller Indices, nReleased 2/23/21	Historical Median Absolute Error*
10-City Composite, nMonth-Over-Month (SA)	1.3%	1.2%	0.2%
10-City Composite, nYear-Over-Year (NSA)	9.5%	9.8%	0.2%
20-City Composite, nMonth-Over-Month (SA)	1.3%	1.3%	0.2%
20-City Composite, nYear-Over-Year (NSA)	9.8%	10.1%	0.1%
U.S. National nMonth-Over-Month (SA)	1.3%	1.3%	0.1%
U.S. National nYear-Over-Year (NSA)	10.3%	10.4%	0.1%
*Calculation of Median Absolute Errors are based on Zillow's forecasts dating to 2011. The national Case-Shiller forecasts began in 2014.

The factors that have, for months, stoked competition for homes remained firmly in place in December. A wave of eager buyers – many of whom are looking to enter the market for the first time – sought to capitalize on record-low mortgage rates and snap up the relatively few homes available for sale, leading homes to fly off the shelves and prices to continue to grow. In some major markets, homes are going under contract more than a month faster than they were this time last year. This forces would-be buyers to move very quickly to put an offer in on a home they desire, increases the likelihood that multiple offers will be fielded by the seller and ultimately places more upward pressure on prices. Looking ahead, with mortgage rates remaining relatively low and the wave of eager buyers continuing to swell, it’s unlikely that this competition for housing, and subsequent strong price appreciation, will meaningfully abate in the near future.

Monthly growth in January as reported by Case-Shiller is expected to slow slightly from December in all three main indices, while annual growth is expected to accelerate across the board. S&P Dow Jones Indices is expected to release data for the January S&P CoreLogic Case-Shiller Indices on Tuesday, March 30.

Index	Actual Dec. nCase-Shiller Change	Zillow's Forecast for the Case-Shiller Jan. Indices
10-City Composite, nMonth-Over-Month (SA)	1.2%	0.9%
10-City Composite, nYear-Over-Year (NSA)	9.8%	10.4%
20-City Composite, nMonth-Over-Month (SA)	1.3%	1.0%
20-City Composite, nYear-Over-Year (NSA)	10.1%	10.7%
U.S. National nMonth-Over-Month (SA)	1.3%	1.1%
U.S. National nYear-Over-Year (NSA)	10.4%	10.9%

Note: Case-Shiller and Case-Shiller Index are registered trademarks of CoreLogic Solutions, LLC. The statements herein are not endorsed by or provided in association or connection with CoreLogic, LLC.