The system has operated 24/7 service every day of the year (barring emergencies and disasters) throughout most of its history; since May 6, 2020, it has been temporarily closed to the public during late nights to disinfect trains and stations due to the COVID-19 pandemic in New York City. By annual ridership, the New York City Subway is the busiest rapid transit system in both the Western Hemisphere and the Western world, as well as the ninth-busiest rapid transit rail system in the world. In 2017, the subway delivered over 1.72 billion rides, averaging approximately 5.6 million daily rides on weekdays and a combined 5.7 million rides each weekend (3.2 million on Saturdays, 2.5 million on Sundays). On September 23, 2014, more than 6.1 million people rode the subway system, establishing the highest single-day ridership since ridership was regularly monitored in 1985.