In June the total number of riders on Caltrain was 1,319,404, an increase of nearly 11 percent over June 2011.
The increased ridership also means increased revenue for Caltrain, which reached more than $10 million this year, 22.1 percent higher than in 2011.
Ridership has increased steadily since 2008, when it dipped due to the economic recession and job loss, which meant fewer commuters on board, according to Caltrain.
Record ridership also meant crowded trains.
To respond to the increased demand Caltrain has announced that it will restore four midday trains, which were eliminated last year due to budget cuts. There will also be two additional evening trains. The new service will begin this fall, according to Caltrain officials.
Caltrain has attributed the significant ridership increase to the introduction of the Baby Bullet express service in 2004, which increased ridership by 17 percent within six months.
Caltrain also attributed the increase in ridership to almost double the number of express trains between San Francisco and San Jose, and the incorporation of transfers into service, which improved ridership by 9.4 percent in five months.
By 2019, Caltrain plans to operate electric trains to meet anticipated, future demand for reliable public transportation.
According to a report released in June by the Bay Area Council Economic Institute, modernizing the Caltrain corridor with electrified trains and updated signal systems could also create 9,600 jobs in the Bay Area.