in Q4 2014, making it the twelfth busiest Light rail system on a per mile basis over this time period. Weekday ridership on the Trolley has been relatively high since Q3 2013 (see table at right). In all of 2014, the San Diego Trolley provided 39,731,900 unlinked passenger transits according to the American Public Transportation Association (APTA). MTS reported that there were 39,694,197 trips on the Trolley in Fiscal Year 2014 (FY 2014), a 34% increase over Fiscal Year 2013. Of the Trolley's three lines, the Blue Line has the system's highest ridership with 15,094,878 riders during FY 2014, followed by the Green Line with 13,673,926 FY 2014 riders, and the Orange Line with 10,896,289 FY 2014 riders. The Silver Line, operating only mid-days just four days a week (and with some service interruptions during the year), carried 29,104 passengers around the downtown loop in FY2014. According to figures from APTA, previous to 2014, the San Diego Trolley achieved the highest level of ridership in 2007, when there were 36,386,100 unlinked passenger transits on the system over that entire year. The Trolley system's highest average weekday ridership of 124,300 was achieved in Q3 2007 – this corresponded to 2,323 passengers per route mile daily. Future Proposed Balboa Park streetcar line MTS began work in March 2011 on a study to evaluate the feasibility of reconnecting Balboa Park, the San Diego Zoo and Downtown San Diego through a fixed-guideway, electrified streetcar line – the final study on the subject was published in October 2012. The project study corridor runs between the City College Trolley Station area, and Balboa Park in the vicinity of the San Diego Zoo. An alignment similar to the proposed one was last served by a streetcar system in 1949 on lines 7 (Park Boulevard-University Avenue to East San Diego) & 11 (Park Boulevard-Adams Avenue to Kensington). The Committee evaluated what types of streetcars to use for this proposed line, the possible options including the recently ordered 57 Ultra Short 2011 S70s in the "Modern Streetcar" category, and the restored PCC Streetcars from the Downtown Silver Line in the "Vintage Streetcar" category. The major construction issue was how to cross I-5 without having to reconstruct the entire bridge. The estimated cost for construction of this line was $68.2 million, with each trolley car estimated to cost between $850,000 (for a restored PCC trolley car) to $3.6 million (for