Over the years, since the mid-1960s, station entrances were closed for various reasons. Entrances started being closed due to increases in crime in the 1960s; needed labor reductions throughout the 1970s; an increase in crime and the need to reduce costs in the 1980s; and in the 1990s the MTA Board approved guidelines to allocate scarce resources by matching station capacity with ridership, which led to additional station entrance closures. This was followed by additional closures due to a 1991 rape in a passageway; followed by closures due to station renovation projects starting in 1994. In 2017, in anticipation of the L shutdown, the MTA started reopening closed entrances in North Brooklyn to reduce crowding.