FILE PHOTO: The Empire State Building rises over lower Manhattan as viewed from the Top of the Rock observation deck in New York, U.S., February 14, 2018. REUTERS/Lucas Jackson

NEW YORK (Reuters) - Apartment sales in Manhattan fell to the lowest monthly rate in January since February 2012 as a declining trend in city-wide sales both by price and volume emerged, listings and data website CityRealty said on Monday.

Across Manhattan, 840 co-ops and condos were sold in January, a 20.1 percent decline from a year earlier, when 1,051 apartment sales were recorded, CityRealty said.

Data from the New York City Department of Finance showed 995 units were sold in December, a 15.6 percent decline, the firm noted.

Sales prices fell 15.5 percent to an average $1.86 million in January from an average $2.2 million a year earlier, while the average price in December fell 14.3 percent, from $2.17 million.

“I’m a little startled, it’s quite a blip,” Gabby Warshawer, director of research at CityRealty, said of the drop.

Data for January showed the lowest number of units sold since February 2012, when 799 sales were recorded at an average price of $1.50 million. Volume peaked in July 2013, when 1,721 units were sold.

One reason for the price decline was a lack of new condo buildings entering the market, where prices in the luxury range well north of $2 million have skewed the overall market, Warshawer said.

Apartment sales priced above $10 million have doubled since 2013, when the post-crisis recovery was fully in swing, CityRealty said in a year-end 2017 report. [nL1N1OB1JP}

The average price of a condo was $2.8 million in January, compared with $1.3 million for co-ops, using data that excludes sales in upper Manhattan because of the area’s low activity. Only 61 units were sold that month in upper Manhattan.