Gov. Martin O'Malley has set a goal of doubling transit use by 2020, but overall transit ridership has increased by only about 14 percent since fiscal year 2006, according to the state. Some lines have grown — on the MARC Penn line, for instance, average weekday ridership jumped from 15,133 in 2003 to 24,350 in 2013. On others, use remains more limited. About 4,300 people rode the Camden line on a weekday in 2013, up from 3,900 in 2003.