By Diana Olick | CNBC.com
For six straight months, home prices have been leaping in double digits from a year ago. In May, the median existing home sale price was 15.4 percent higher nationally than May of 2012, according to a new report from the National Association of Realtors.
The Realtors themselves say that kind of jump is "unsustainable."
"Some of the increases can be explained by the fact that it is recovering from an over-corrected situation," said Lawrence Yun, chief economist for the Realtors. "But with people's income rising at only 1 or 2 percent and prices rising in double digits, it cannot continue."
Part of the steep rise in the median home price can be attributed to a change in the mix of homes that are selling. Sales of homes…