SAN FRANCISCO (CBS SF) – December Bay Area home sales and prices moved in opposite directions on a year-over-year basis, research firm CoreLogic announced.

New and existing home sales fell 9.1 percent to 7,136 sales while the median home prices jumped 4 percent.

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“Last month, the San Francisco Bay Area’s housing market posted its largest year-over-year sales decline since last July, but there’s a caveat,” CoreLogic research analyst Andrew LePage said in a statement.

“The number of deals recorded in December 2015 was artificially high – the result of then-new federal mortgage rules that caused delays for many transactions that normally would have closed the prior month.”

LePage also attributed the decline to one less business day in December 2016 compared with the previous year and possibly to the increase in mortgage rates in November.

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On prices, LePage said the 4 percent increase is lower than the average gain of 6.4 percent over the last two years and down from a 12.1 percent year-over-year increase in December 2015.

“The moderation of home price growth comes as no surprise given the severe affordability constraints would-be buyers face in much of the region, as well as the absence of the type of risky loans that allowed many buyers during the last housing boom to purchase homes they couldn’t afford long-term,” LePage said.

The median price in the Bay Area was $676,000 in December up from $650,000 in December 2015, according to CoreLogic. Year-over-year, the median price has risen for 57 consecutive months.

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