Bill’s money pit

Another budget from Mayor de Blasio. Another wild lowball on the ever-upwardspiraling cost of sheltering New York City’s record numbers of homeless. And no hiding from the facts: New York City is likely to spend $1.4 billion in the coming year housing upwards of 60,000 people a night in hotels, apartments, drill halls and shelters in the year to come.

That huge number is still nearly $200 million less than what the city’s homeless shelters are actually likely to cost.

So concludes the city’s Independent Budget Office, combing through the mayor’s preliminary budget for fiscal year 2018, which begins in July, to affirm a calamity both human and financial that can’t be papered over with mathematic acrobatics.

And yet time after time, de Blasio tries to do exactly that.

Each November since taking office, the mayor’s money minders have cracked open the budget midway through the city’s fiscal year, to pile on tens of millions of dollars more for the bills that still must be paid to hotel operators and landlords offering expensive and often run-down lodgings — such as the apartment where a faulty radiator valve fatally scalded two toddlers in December.

Every year, the extra amount of funding ladled on gets bigger and bigger. And every year, de Blasio offers a self-serving explanation for optimism nowhere in the numbers.

In 2014, he started by lowering projected spending by about $50 million. Why? He planned a joint city-state subsidy program to help the homeless pay for permanent apartments, moving thousands swiftly out of shelter — and stuck with his projections even once it became clear Gov. Cuomo was not on board. Ultimate cost: $92 million more than planned.

In 2015, de Blasio introduced rent-aid programs on his own, but not with enough speed or funding to keep pace with the numbers of people streaming into shelters, the IBO found then. Ultimate cost: $170 million more than planned.

In 2016, the mayor again assumed an imminent decline in shelter spending as he revved up funding for permanent housing — which will take years to come online. Ultimate cost: still unknown, after $115 million added in November and another $140 million shoehorned in last month.

The excuse this time? A comprehensive homelessness plan still to be announced by the mayor — a year after his social services czar, Steve Banks, ended a review of the Department of Homeless Services and unveiled a stack of reforms.

Try, try again.