Government-sponsored mortgage company Freddie Mac's housing index showed a softened national market in March, with a -3.06 overall score and almost no improvement over the last three months. Less than half of the states and metro areas measured showed stable levels of housing activity.

Mortgage giant Freddie Mac's Multi-Indicator Market Index (MiMi) for March, released on May 28, shows a largely stalled housing market compared to the prior month and year-ago levels. The few markets that are improving, or showing a stable range of housing activity, are benefiting from the energy-related growth taking place along the country's mid-section.

Only 10 states and the District of Columbia were stable in March, according to the index, and just four of the 50 metro areas included in the index – Austin, Houston, New Orleans and San Antonio – were similarly positive. Overall, 13 of the 50 states plus the District of Columbia are improving based on their three-month trend, and 20 of the 50 metros show increases over the same span.

"Less than half of the housing markets MiMi covers are showing an improving trend, whereas at this same time last year, more than 90 percent of these same markets were headed in the right direction," Freddie Mac chief economist Frank Nothaft said in a statement. "We're hopeful that many of these markets that have stalled will start moving again, now that mortgage rates have eased over the past month and the spring home buying season is upon us."

The national MiMi value in March stands at, with only a slight improvement (+0.03 points) from February to March, and a three-month flat trend (+0.05 points). On a year-over-year basis, however, the market has improved by 0.66 points. The lowest MiMi score on record, -4.49 points, was set in November 2010 when the housing market was at its weakest.