While the OFHEO index increases almost everywhere, the Case-Shiller index declined Jan-Feb in every single city measured.
On this blog, we have considered various reasons why the two indices would be different. But I cannot honestly say that we have an explanation for the two indices' disagreements over the past few months.
For example, Professor Nunes pointed out that Case-Shiller puts a lot of weight on the more expensive housing areas. But now Case-Shiller and OFHEO disagree on a region-by-region basis.