When maintenance shut down the Manhattan-Brooklyn artery over Black Friday weekend, local businesses suffered, many reporting a severe drop in sales compared to the same weekend last year.

Since July, the Metropolitan Transportation Authority has completely or partially shut down service on the L on a dozen weekends. The weekend after Black Friday was the worst, though. Merchants reported that business slumped 20% to 80% from last year's levels. In response, they've begun meeting with community leaders and reaching out to local politicians and the MTA to figure out alternatives.

Shoddy L train service is nothing new, of course, as sporadic weekend schedules and delays have plagued the borough's burgeoning hipster population for years. Only recently, however, have local businesses calibrated the financial effects of suspended train service, particularly on weekends.

People are typically lined up around the block for tours of the Brooklyn Brewery on Saturdays and Sundays. Owner Steve Hindy said that when the L is out of commission, sales typically slip about 20%. Similarly, at jewelry shop Brooklyn Charm just a few blocks away off Bedford Avenue, owner Tracie Campbell estimated that as many as 40 transactions were lost on each of the two days after Black Friday.