MassDOT reports that ridership on the only only-in-Boston commuter rail line increased 25% during the first of two fare-free weeks in May - and 44% the second week - but then dropped back down to normal light levels when the fares came back.

US Rep. Michael Capuano contributed roughly $50,000 from his congressional campaign coffers to fund the experiment, aimed at promoting use of the line, on which the state is spending more than $100 million to add more and new stations.

According to MassDOT:

An increase in total trips occurred during the two-week period, though this increase did not extend after the sponsored service expired. During the first week of the program, the number of weekday trips increased by approximately twenty-five percent (an additional 550 one-way trips per day or fourteen passengers per train) compared to the week before. The second week of the free-fare period showed an increase of forty-four percent from the week before the program. This is approximately 1,000 additional one-way trips per day or twenty-five more passengers per train. In the inbound direction, the additional trips were primarily in the morning peak and at 4 p.m. In the outbound direction, the additional trips were primarily in the afternoon peak and early afternoon.

Despite ridership falling back to non-free levels, advocates remained optimistic more people will eventually find their way to the commuter line, which has subway-levels fees, except at the end of the line at Readville - especially if the T increases the frequency of trains. In a statement, the Fairmount Indigo Transit Coalition said:

The Fairmount Indigo Transit Coalition appreciates Congressman Capuano’s bold step of sponsoring free rides to demonstrate the need for strong service on the Fairmount/Indigo Line. The FITC is excited about how our community mobilized to support bringing about a dramatic increase in ridership during the two weeks of sponsored free rides. We look forward to continuing to work with our elected officials, the City, and MassDOT/MBTA to improve service and make the Fairmount Line the best possible.

Earlier:

Report lists ways to put the Fairmount Line on the map.