In the last two rounds of contract negotiations, the PBA has shown that New York City police officers have been doing more work than ever, even with nearly 4,000 fewer cops, and that we deserve part of the money saved by the work-force reduction. But the city says it doesn’t consider that a productivity improvement — at least not when cops are involved.

But what about sanitation workers? Certainly, nobody discounts the important and difficult work our brothers and sisters in green do to keep this city clean and healthy. They work hard under difficult circumstances.

It’s not widely known, but a sanitation worker doing the primary job for which he or she was hired — picking up household refuse — is paid a bonus of $47 a shift. Under the most recent contract, sanitation workers also receive an additional $5 a shift for dumping their trucks at the end of their route. Those bonuses came about as a result of collective bargaining gain-sharing agreements over the years.

The city is quick to point out that the reduction of three-person to two-person crews on household collection while doing the same work resulted in a quantifiable savings that was shared with the two-person crews.

Then, the city claims that additional bonuses were granted to those two-person crews through a productivity-improvement plan they called “route extension,” whereby the two-person crews’ collection routes were lengthened and the workers collected a share of the savings.

Finally, the city quantified the amount of money saved by having a truck dumped on the day shift instead of having a night-shift spend the evening driving back and forth to dump trucks, and paid the $5-a-day bonus for dumping on the day shift.

In simple language, sanitation workers are doing more work with fewer people, and they are sharing in the savings from the reduced headcount. (No wonder some police officers are quitting to take jobs as sanitation workers — see Joe Maccone’s “Your pension questions answered.”)

Why, we ask the city, is a reduced headcount worth more in the Department of Sanitation than it is in the NYPD? Sounds like a double standard to me.

Everybody agrees that the NYPD and its police officers have been doing more with less. Economists and officials alike cite crime reductions and safe streets as the principal reasons for New York City’s economic recovery. The city admits that police officers have taken on added anti-terrorism responsibilities. It accepted a mayoral commission’s suggestions to require more education for police officers and to increase the minimum age for coming on the job. But in every one of these examples it has refused to share the savings with its police officers because, they say, they can’t quantify those savings.

They are essentially saying to us that there is no quantifiable value to deterring crime, to risking one’s life for one’s fellow New Yorker, for being a more educated police officer, for fighting terrorism successfully — in short, for doing a lot more police work for less. It’s about time the city figured out how to compensate its police officers for the valuable and important work we do, considerable risks we take, and the efficient and effective way we discharge our duties.