The Case-Shiller Index is a popular reporting tool for the nation's home prices. Each month, researchers measure home values in 20 large cities, compile their findings, and then publish them to the public.
The Case-Shiller Index is not a perfect measurement by any means. It gives more weight to expensive homes than inexpensive ones, for example, and its sample set includes just 37 states. But that doesn't diminish its importance to the housing sector.
Because the Case-Shiller Index comes from the private sector, it's an excellent counter for the U.S. government's home value reporting tool -- the House Price Index.
In this current market, the Case-Shiller Index tends to report housing in a more negative light than does the government. This doesn't make either method more accurate, it just provides a helpful point/counter-point.
And that's why February's Case-Shiller Index is so important.
Despite reporting falling values in each of its 20 tracked cities, the Case-Shiller Index showed values falling with a lesser speed and intensity than in months prior.
It's a small victory, but if the Case-Shiller Index shows that home prices are starting to mend, you have to pay attention -- especially because the index is on a 2-month delay and doesn't account for Spring Buyers or the $8,000 first-time homebuyer tax credit.
One month doesn't make a trend, but if often-negative Case-Shiller Index turns in similar numbers for March, it could be the signal that housing has bottomed.