OAKLAND (CBS SF) — BART’s ridership losses remained mostly steady last week as the agency plans to roll out reduced service hours Monday and until further notice amid the Bay Area’s shelter-in-place order due to the spread of the novel coronavirus.

Ridership throughout the BART system was down between 87 percent and 89 percent from Tuesday to Sunday when compared to average ridership in February.

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BART officials estimate the ridership and fare revenue losses and reduced economic activity during the shelter-in-place order could cost the agency $57 million each month.

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Starting Monday, weekday BART service will reduce from 5 a.m. to midnight to 5 a.m. to 9 p.m. Service on Saturdays and Sundays will also reduce from 6 a.m. to midnight Saturday and 8 a.m. to midnight Sunday to 8 a.m. to 9 p.m. on both days. Train frequency is not expected to change, according to the agency.

BART staff are working to update the agency’s Trip Planner tool to reflect the new service schedule, with canceled trains crossed out in red. The agency will also indicate transit alternatives on the Trip Planner.

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BART officials continue to work with local, state and federal officials to secure funding support to shore up the agency’s revenue losses during the ongoing coronavirus outbreak.