Home prices in the U.S. rose 0.8 percent between June and July, marking the fourth consecutive monthly increase, the Federal Housing Finance Agency (FHFA) said Thursday.

The agency’s House Price Index (HPI) has been trending upward since April of this year. That string of gains is coming off a streak of declines that was three times as long. Prior to April, FHFA’s HPI had been on a slippery downward slope for 12 straight months, going back to May 2010.

The federal agency’s index is calculated using purchase prices of houses backing mortgages that have been sold to or guaranteed by Fannie Mae and Freddie Mac.

Looking at the 12 months ending in July, U.S. homes lost 3.3 percent of their value, according to FHFA’s assessment.

The July index reading is 18.4 percent below its April 2007 peak and roughly the same as the March 2004 index level.

Among the nine census regions, the biggest monthly gain was seen in the West North Central division – which includes the Dakotas, Minnesota, Nebraska, Iowa, Kansas, and Missouri. There, home prices rose 3.6 percent between June and July.

The South Atlantic division – Delaware, Maryland, District of Columbia, Virginia, West Virginia, North Carolina, South Carolina, Georgia, and Florida – saw the biggest decline for the month, down 0.4 percent.

The West North Central division was the only region to experience a price increase over the last 12 months, posting an annual gain of 0.2 percent.