by Calculated Risk on 5/28/2012 02:11:00 PM

The following graphs show the number of cities with increasing house prices on a year-over-year, six month, and month-over-month basis.

The first graph is based on the Case-Shiller Composite 20 cities using seasonally adjusted data starting in January 2007.

There were still a few cities with increasing prices in early 2007. The increases in 2009 and 2010 were related to the housing tax credit (all of those gains and more are gone).

Recently prices have started increasing in more and more cities again. Note: Case-Shiller data is through February, Zillow data is through April.

Click on graph for larger image in graph gallery.

The second graph shows the same year-over-year, six month, and month-over-month price increases for the 166 cities tracked by Zillow.

The pattern is similar to the Case-Shiller Composite 20 cities.

I expect that the number of cities with a year-over-year price increase will continue to climb all year, and later this year the Case-Shiller Composite 20 index (and Zillow national index) will turn positive on a year-over-year basis.

In February, the Case-Shiller Composite 20 index was down 3.4% year-over-year, down 2.5% over the last six months, and up slightly in February. The March data will be released this coming Tuesday.

The Zillow national index was down 1.4% year-over-year in April, only down 0.4% over the last six months, and up 0.7% month-over-month. This index will probably turn positive year-over-year in a few months.