Since the late 20th century, the MTA has started several projects to maintain and improve the subway. In the 1990s, it started converting the BMT Canarsie Line to use communications-based train control, utilizing a moving block signal system that allowed more trains to use the tracks and thus increasing passenger capacity. After the Canarsie Line tests were successful, the MTA expanded the automation program in the 2000s and 2010s to include other lines. As part of another program called FASTRACK, the MTA started closing sections of lines during weekday nights in 2012,