The average homeowner's estimate of how much their property was worth deviated slightly from appraised values in December, according to the retail mortgage lender Quicken Loans. However, value perceptions were significantly improved from last year and remained within half a percentage point of the appraised figure.

In its Home Price Perception Index for December, Quicken Loans found that the typical appraisal was 0.45 percent less than the value estimated by a homeowner. This was up from a 0.36 percent difference in November, but down from a 1.19 percent difference in December 2017. Homeowner estimates have been within 0.5 percent of appraised values on average since March 2018.

The monthly analysis also assigns an index for four geographical regions and 27 major metropolitan areas. On average, appraisals fell 0.58 percent short of expectations in the Northeast, 0.48 percent lower in the Midwest, 0.42 percent lower in the South, and 0.34 percent lower in the West.

The average appraisal in the Boston metropolitan areas was 2.98 percent higher than expected, while appraised values were typically 2.36 percent higher in Denver and 2.23 percent higher in Charlotte, N.C. Average appraisals were less than expected in nine metro areas, with the largest gaps in Chicago (1.96 percent lower), Cleveland (1.33 percent lower), and Philadelphia (1.31 percent lower).

Bill Banfield, executive vice president of capital markets at Quicken Loans, said home equity can be an untapped source of revenue in many markets, particularly areas where values are higher than expected. Based on median home values and the latest index, the typical Boston homeowner would have $15,000 more in equity than originally expected.

"Many consumers don't think about their home's value until they start thinking about selling it," said Banfield. "They may not be watching their local housing market as closely as appraisers who are reviewing home sales every day – leading the owners to incorrectly estimate their home's value. The fact of the matter is that there are many ways a homeowner can make their equity work for them if they have a realistic estimate of their home's value. Tapping into home equity to consolidate high interest debt or make home improvements are very popular options right now."

Quicken Loans also issues a monthly update to its Home Value Index, which compares current home values to those in January 2005. An index of 100 indicates that values are equal to those recorded in this month.

The national index in December stood at 111.22. This index was up 0.79 percent from the previous month and 5.15 percent from the previous year.

The index in the Northeast was 103.4, up 0.52 percent from November and 4.41 percent from December 2017. The Midwest had a 0.37 percent increase from the previous month and a year-over-year increase of 4.88 percent for an index of 91.47.

The Home Value Index in the West ticked up 0.38 percent from November and 5.98 percent from December 2017 to 135.57. In the South, the index stood at 112.87 – an increase of 0.54 percent from the previous month and 4.86 percent from the previous year.

"Any consumer who has read recent news about the housing market and has the impression that it is slowing to a halt should see that the HVI proves that this could not be farther from the truth," said Banfield. "Home value growth is not at a more normal, sustainable clip – keeping pace with inflation and wage growth more than we have seen in the past few years."

The Home Price Perception Index is based on a national database of refinance mortgages, which compare a homeowner's estimate of their property's value to an appraisal performed later in the process. The Home Value Index is based on both purchase and refinance mortgages.