Making sense of home prices

Every so often, we read headlines about housing prices (seems like every other headline is about housing prices these days), and they all seem to contradict each other. Why is it that while NAR numbers say we are flat-to-mildly-decreasing, the Case-Schiller index states that we are decreasing? Which numbers do we trust, and why are they so different?

To start, there are 3 major indeces:

1. OFHEO (Office of Federal Housing Enterprise Oversight – they regulate Fannie Mae and Freddie Mac)
2. S&P / Case-Shiller index
3. National Association of Realtors (NAR)

1) OFHEO looks at existing home sales and excludes new home purchases. In addition, it only looks at conforming loans, ignoring transactions that are not guaranteed by Fannie and Freddie. Homes with non-conforming mortgages are seeing larger price declines than the homes that OFHEO tracks. So this means that the numbers that OFHEO reports are not as volatile as the rest of the indeces. To make matters even more complicated, OFHEO also considers appraisals that are generated when people refinance their homes, which is almost always different from the purchase price, and is a truer indication of market value.

2) Similar to OFHEO, Case-Shiller looks at existing home sales and excludes new home purchases. Although there are actually three Case-Shiller indeces (monthly 10-city survey,  monthly 20-city survey, and a quarterly report that looks at all nine U.S. Census regions), the one that makes it to headlines most often is the monthly 20-city survey. In addition to already being more volatile than OFHEO, this survey can be even more misleading as a proxy for the national situation, as it looks at only 20 metropolitan statistical areas.  It just so happens that these areas include some of hardest-hit areas as far as price declines, such as Detroit, Las Vegas, Los Angeles, Miami, Phoenix, San Diego and Washington, D.C. Additionally, Case-Shiller can miss trends in micro-markets, as it doesn’t consider sales of condos and co-ops. So, next time that you are tempted to get worked up over Case-Schiller numbers, don’t. Especially if it’s the monthly survey.

3) NAR’s methodology is much more straightforward.  It looks at sales of existing homes listed by MLSs, and reports median home prices.  As we know, there can be a disconnect between a sales price and a home value. In addition, NAR considers median prices only, reducing the impact of price volatility in upper price ranges.

Case in point: Freddie Mac home-price index indicateed that housing in New York state fell just over 4 percent in value in the past year. Meanwhile, the Case-Shiller index tells a different story, indicating that New York’s home prices are down roughly 15 to 16 percent from their high.

Source: To make sense of the home price indeces, I used a very well written analysis written by Matt Carter for Inman News