and federal sources, largely sales tax revenue collected by the three JPA signatories, while farebox revenues account for about one-third of costs. Cost sharing for capital projects, excluding stations, during the initial 36 months of service was determined by the JPA on a case-by-case basis and approved by each of the member agencies. The initial purchase of rolling stock, construction of stations, and other start-up costs, amounting to some $48 million, were covered primarily by Measure K funds. Station improvements are the responsibility of the county in which the station is located. ACE pays the Union Pacific Railroad about $1.5 million per year to use their tracks. ACE trains also use about of Caltrain track in San Jose. Service began on October 19, 1998, with two daily round trips running to San Jose in the morning and Stockton in the evening. Service expansion The original service used two trainsets, each with four bilevel coach cars, for a total seated capacity of 1,120 passengers in each direction daily. In September 1999, less than a year after opening, the service reached 1,000 daily riders per direction, near full capacity. With that success, the agency wanted to add additional runs. To enable more trains on the line, ACE funded $3 million in track improvements, but the limited amount of equipment only allowed ACE to add a morning "short turn" run between San Jose and Pleasanton. This "turn-back train" started service on February 21, 2000, and gave Pleasanton and Fremont a third inbound train to alleviate the crowding on the two earlier trains. Even with the added capacity, by early 2001 ACE was regularly carrying more than 700 daily standees. ACE purchased additional equipment, allowing the "turn-back train" to operate to Lathrop/Manteca station, nearly the full length of the route, beginning on March 5, 2001; trains also began stopping at Santa Clara station. Although the third train added 560 seats in each direction, it brought an immediate increase of 380 daily riders. ACE then planned to add a fourth round trip later in the year, with fifth and sixth round trips by 2006. However, by late 2001, the deepening dot-com recession was severely hurting ridership, and expansion plans were put on hold. On June 30, 2003, the ACE JPA was dissolved in favor of a Cooperative Services Agreement between the three member agencies. On January 6, 2003, ACE introduced the Stockton Solution Shuttle, allowing