Long Island’s final 2015 sales tax revenue limped in Thursday with Nassau posting only a 1.2 percent gain for the year, or $13 million, while Suffolk rose even less — .87 percent for a $1.7 million gain.

Officials in both counties attributed the poor performance to both lagging economic growth, minimal wage gains, a shift to out-of-state online shopping and significant drops in gasoline prices.

Suffolk officials last fall dropped their year-end sales tax estimates for 2015 and 2016 by $30 million for the county’s adopted 2016 budget. But the county budget is still optimistic, forecasting 3.75 percent growth for the coming year.

Nassau officials say their 2015 sales tax revenue came in $39.5 million below what was adopted in the 2015 budget. The county said it has factored in the $39.5 million sales tax loss in its projection that showed Nassau ending 2015 with a $45 million surplus. But NIFA says Nassau used $147 million in nonrecurring revenue in 2015, including borrowing and taking money from reserves.

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NIFA member Chris Wright, a frequent critic of Nassau budgeting practices, said, “Based on the county’s track record, announcements of an existence of a surplus at this point are completely ignorable. Everyone knows that the county ran a deficit . . .”

“The days of double-digit sales tax growth are long gone,” Suffolk Deputy County Executive Jon Schneider said. “But no one is praying for the return of $4 a gallon gasoline.”