SOUTHWEST HARBOR – Selectmen on Wednesday set the property tax rate at $14.50 per $1,000 in value, but a computer glitch will require them to rethink it, assessor John Doan says.

Doan said Thursday that the town’s computer system counted two tax-exempt properties as taxable, which will throw off the numbers “slightly.”

Selectmen also approved a budget overlay of $87,364 and set the property tax rate at 14.5 mills, up from 13.9 mills for the current fiscal year. Under law, a town can set aside up to 5 percent of its total budget as an “overlay,” or cushion, but Town Manager Ken Minier and others said the higher figure was more than needed.

Minier said 5 percent of the town budget represents $240,000.

Doan said he needs to meet with Minier about the computer problem and redo the final tax base and mill rate figures.

The town’s tax base increased about $6 million in the past year, Doan said, thanks in large part to construction of several bulk-storage buildings, a storage warehouse and two large homes.

The town’s total assessed value is $335.4 million, but that number also will change slightly when the tax-exempt properties are removed from the total, Doan said.