U.S. house prices remained on an upward track in May on a seasonally-adjusted basis, the Federal Housing Finance Agency (FHFA) reported Tuesday. House prices in May were 0.7 percent higher than a month earlier, according to the FHFA\'s monthly House Price Index. Over the 12 months ending in May, the house prices rose 7.3 percent, indicating a steady improvement in the U.S. housing market. However, the price variation across the country was ragged in May. For the nine census divisions, the prices of the South Atlantic division, including Delaware, Maryland, District of Columbia, Virginia, West Virginia, North Carolina, South Carolina, Georgia and Florida, climbed the most by 1.8 percent from January, while the prices of the East South Central division, including Kentucky, Tennessee, Mississippi, Alabama, decreased 1.5 percent. The FHFA also noted that the house prices in May were still 11. 2 percent below the April 2007 peak level and roughly the same as the January 2005 level. The FHFA measured changes in real estate values using purchases of properties with mortgages backed by Fannie Mae or Freddie Mac. It did not provide a specific price for houses. The U.S. National Association of Realtors reported Monday that the median existing home price for all housing types jumped to 214, 200 dollars in June, up 13.5 percent from a year earlier. This marks 16 consecutive months of year-over-year price increases.