Interim Town Manager Jim Bennett last week presented a proposed municipal operating budget for next year that was less than the current year’s, offering good news to a town stung by a big budget increase last year.

But after calculation errors and missing information were discovered, the proposed municipal budget is now $13.6 million and that has pushed the town’s proposed tax rate above the current year’s tax rate, according to Bennett.

Despite the proposed budget still being lower than the current year’s budget, which is nearly $14 million, the tax rate for the proposed budget is $17.64, or 39 cents above the current tax rate of $17.25, according to Bennet’s calculations.

Though that calculation assumed that the school and county budgets would remain the same — an unlikely scenario — it was a way for Bennett to show the impact on taxpayers of the proposed municipal portion of the budget.

After miscalculations in previous budget years drove up the current year’s town budget, leading to steep property tax increases, councilors tasked Bennett with putting forward a modest budget, keeping increases as low as possible.

Bennet’s initial proposed budget,which was a little more than $13 million, had an estimated tax rate of $17.03 per $1,000 of assessed property value, which would have been a 22-cent decrease compared to this year.

But roughly eight line items in the proposed budget had to be adjusted. A few of them were adjusted down, but ultimately the adjustments increased the proposed budget by $628,932.

The biggest error involved streetlights and hydrant rentals, originally budgeted for $104,000. Because some costs were left out, the amount is now $682,978. The animal control line went up $44,404. Public Works went up $32,277.

The overall increase of all eight line items adjusted up was $786,793. However, Bennett adjusted five line items down, amounting to $157,861, which helped to offset that increase.

The mistakes are largely attributed to spreadsheet errors, the computer program used to aggregate and calculate all budget items, and one expense that was accidentally left out of calculations altogether, according to meeting documents Bennett prepared for a March 5 budget workshop.

“The budget was completed this year in a set of integrated spreadsheets,” Bennett wrote. “It has advantages that it provides the ability to drive the calculations quickly. It also organizes the information easier to provide more insight into the budget relationship. At the same time, if a link or formula is broken, it will cause mistakes.”

Ahead of the March 3 council meeting where Bennett first presented his proposed budget, he made last-minute changes to budget items on the spreadsheet, which led to issues with links within the document and ultimately the miscalculations, he said Thursday afternoon.

He acknowledges now that he should have waited to adjust those calculations and to present them in future budget workshops, he said.

“We really wanted to make sure we didn’t have any errors going into the process — that happened,” he said. “So all I can do is apologize that that number (street lights and hydrant rentals) got left off.”

Councilors will meet again Thursday night, when Bennett expects to propose about $100,000 worth of adjustments to bring the proposed budget down further, he said Thursday afternoon.

Residents are being encouraged to attend Tuesday’s council meeting to let councilors know how they feel about the current budget proposal. Councilors will meet twice a week for most of April to deliberate over the budget, Bennett said.