Metro ridership looked like a roller coaster Tuesday as it saw less crowded trains and buses.

In Tuesday morning’s commute, rail ridership was down roughly 10 percent to 238,500 riders, compared to the same period a week ago. By midday, some federal workers who had come into their offices for a few hours in the morning headed home. That led to a slight spike in Metro’s midday rail ridership. About 50,000 rode the system between noon and 2 p.m. Tuesday, compared to 40,000 who rode during the same period a week ago.

On Metrobus, there were not immediate numbers available on ridership because data from each bus has to be dumped at the end of the day into a database.