Even as he insists that the city cannot give teachers a retroactive raise, Mayor Bloomberg is trying to soften the blow with what he says has been a nice consolation prize.

“They’ve been getting raises all throughout this period,” Bloomberg said this morning on his weekly radio appearance, referring to the nearly four years since teachers’ current contract expired.

It’s a point that Bloomberg has tried to get across during a two-day campaign about what he says is the city’s perilous financial situation that he began with his final budget proposal. He said the city is already struggling to cover rising healthcare and pension costs for its public workforce and can’t afford the billions of dollars a year it would take to offer retroactive raises on top of that.

Plus, he said, the city is already laying out more for each employee — and he has singled out teachers as receiving particularly generous pay increases in the time that they have been without a new contract. While the average “raise” for all city employees has been 3 percent, teachers “get on average 3.8 percent increase every single year,” he said today.

But teachers say they haven’t gotten a raise in years. So what was Bloomberg talking about? Indeed, the figure Bloomberg cited doesn’t mean what most employees imagine when they hear they’re getting a raise. A city spokeswoman later clarified that the number reflects the city’s increased spending on teachers’ pension and healthcare benefits. Those costs, which are generally rise faster than salaries, turn into benefits for teachers but never show up in their paycheck.

The city’s $8 billion pension costs are projected to increase by more than 4 percent over three years. Healthcare costs, which this year were $6.6 billion, are projected to increase by nearly 30 percent over the same period.

Yet it is also true that many teachers are earning more than they did four years ago, because of the salary steps that are built into the teachers union’s contract with the city. Those salary steps mean that teachers and other school workers see their salaries inch up as they put in more time in the classroom and earn more credits toward advanced degrees. For instance, first time teachers starting off at $45,530 receive a nearly 7 percent raise worth $3,306 after completing two years in the classroom. Another three years of work is worth a 2.6 percent bump, or $1,317 (The UFT’s current salary schedule is here).

Even though Bloomberg seemed like he was trying to make teachers feel better about their compensation, he didn’t miss an opportunity to take a swipe at their union.

“Our unions are usually very cooperative. One sort of a lot less, but that’s okay,” Bloomberg said, prefacing the comments about the teachers’ pay raises.

A union spokesman declined to comment directly on Bloomberg’s characterization of teachers’ pay raises. But he did provide a statement from Bloomberg’s longtime foe UFT President Michael Mulgrew: “As the mayor’s final term slips away, so does his grip on reality.”