BOSTON – This past summer was a little smoggier than last year, but air quality in New England continues to improve over time.

Environmental Protection Agency officials say the region experienced 26 days between May and September where ozone monitors registered concentrations considered unhealthy.

That’s compared with 16 days in 2006 during the same months.

Most of the unhealthy days this year, 20, were recorded in Massachusetts.

Maine had eight unhealthy ozone days this summer, compared with two in 2006.

Officials say the increase in the number of days with unhealthy air is related to the increase in the number of hot days this year.

Over the long-term, New England has experienced a decreasing number of unhealthy ozone days. In 1983, New England had 90 unhealthy days, compared with 26 this summer.