ALBANY – Slowing population growth in the city and its suburbs last year caused a first-in-a-decade decline in New York’s overall population, census data released Thursday revealed.

Population in New York’s downstate region — the city, Long Island and Lower Hudson Valley — grew by only 21,540 during the 12-month period that ended July 1, 2016, according to the data.

The downstate growth was half of what it was in the region during the previous year and not enough to overcome upstate New York’s continuing loss of population.

“You put all that together and you have a shrinking population,” said E.J. McMahon of the Empire Center for Public Policy.

McMahon said New York’s downstate population growth slowed largely because growing numbers of people are leaving the region.

Net migration from the city and its suburbs totaled 149,331 people during the year, up from 118,262 the previous year, the data showed.

Downstate population totaled 13.47 million as of July 1 and the city’s population totaled 8.53 million, an increase of 21,171 from the previous year, according to the data.

Statewide, population fell from 19,747,183 in 2015 to 19,745,289 as of July 1, 2016.

“Population is really the ultimate benchmark,” McMahon said. “If you are not attracting or retaining people, it is a sign that something is wrong.”

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