A new study this week finds that a regional carbon cap and trade system has saved hundreds of lives and billions of dollars for New Englanders. Officials from the nine participating states are currently working out the future of the program.

The Regional Greenhouse Gas Initiative (RGGI, pronounced Reggie, for short) began in 2009. There are nine member states – all six New England states, plus New York, Delaware, and Maryland – that collectively set caps on greenhouse gas emissions, and then auctions off allowances for power plants to produce such carbon emissions. To date, participating states have cut emissions by 37% - two and a half times more than non-RGGI states.

Recent assessments of the program have shown none of the negative economic impacts that some feared at the outset. In contrast, economies in RGGI states have actually grown faster than in other states. Electricity costs have declined by a few percent, on average. And, the cap and trade program has generated $2.5 billion in revenue for participating states.

Now, a new study says it has also produced health benefits. It’s a logical conclusion; power plants that emit greenhouse gases also produce particulate air pollution that is linked to adverse health effects, such as asthma, respiratory illnesses, and heart attacks. Conversely, limits on greenhouse gas emissions would be expected to reduce air pollution and their related health impacts.

Abt Associates used mathematical models to estimate the scale of such health benefits, and found that RGGI has averted:

Since people who are sick (or worse, dead) can’t work, these health benefits also have ramifications for workforce productivity. Abt Associates estimates that the avoided health problems resulted in somewhere between 39,000 and 47,000 regained work days.

Between the savings in health care costs and the restored productivity, Abt Associates says RGGI has saved participating states some $5.7 billion.

That’s information RGGI supporters hope officials will factor in as they decide the future of the program. Current emissions caps expire in 2020, and the participating states are currently working to set new caps for 2021-2030. It had been hoped that a new plan, or at least proposal, would be in place by the end of 2016. The process has been delayed by a few months, in part to allow participating states to explore options if President Obama’s Clean Power Plan is struck down in the courts or abandoned by the incoming Trump administration.

Still, RGGI hasn’t fallen off the radar. Earlier this week, New York Governor Andrew Cuomo pledged to cut the RGGI carbon cap by 30 percent by 2030. That would be roughly 3 percent per year between 2021 and 2030. That’s less than the 5 percent annual reduction RGGI states have been averaging since 2005.

Last fall, Massachusetts Governor Charlie Baker called for maintaining the annual 5 percent reductions through 2030. This week, Peter Lorenz, a spokesperson for the Baker administration, said they remain committed to RGGI and the “objective of reducing carbon emissions while stabilizing energy bills, preserving electricity system reliability, and creating local jobs and economic growth.”