BOSTON (AP) — State transportation officials say they're on schedule to wrap up work related to the removal of old toll booths on the Massachusetts Turnpike by the end of the year.

The Massachusetts Department of Transportation began demolishing tolls and reconfiguring roadways at 23 locations along the I-90 highway between New York and Boston one year ago Saturday.

The state shuttered the familiar manned toll booths on Oct. 28, 2016 and transitioned to an all-electronic tolling system using E-Z Pass transponders.

Officials say the new system has seen about half a billion transactions, with approximately 86 percent coming from drivers with a Massachusetts transponder that gives them a toll discount.

Drivers without an EZ Pass transponder are billed by mail for their tolls, but they pay more.