Cosi stock fell sharply Wednesday after a bad case of divine intervention.
The fast casual chain earlier reported comparable-restaurant sales at company-owned locations dove 4.5 percent for the four weeks ended Sept. 28 compared to a year ago.
"Business interruptions resulting from the pope's visit on Sept. 22–26, 2015, negatively impacted 30 percent of our company-owned restaurants," the company said in a release detailing the sales downturn.
Cosi, which has 79 company-owned and 30 franchise restaurants operating in 15 states, the District of Columbia, Costa Rica and the United Arab Emirates, has an outsize presence in the New York, Philadelphia and D.C. areas, where Pope Francis visited in September.
Disruptions from the visit shaved off an estimated 0.9 percent from the four-week period and 0.3 percent from 13-week period, Cosi said.
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Shares were more than 16 percent lower Wednesday while the larger market was generally positive. Year to date, the microcap stock has dropped 44 percent.