Updated: July 17, 2019 at 3:13 p.m.

A transportation report released Wednesday conferred the Metrobus service with a D-minus letter grade, WTOP reported.

The report card – co-sponsored by the Coalition for Smarter Growth, a DMV-based organization that promotes mass-transit usage – states that the Metrobus frequently operates behind schedule and is often stuck in traffic. Of the 34 routes analyzed for average speed and adherence to the bus schedule, 18 routes were assigned F’s, five routes earned D’s, 10 routes scored C’s, and one route obtained a B, but no routes received an A grade.

“The results of this analysis paint a striking picture of the problems Metrobus encounters on a daily basis: on these high-priority routes, service was found to be largely unreliable and unpredictable, with buses regularly arriving much later than scheduled and headways rarely being maintained,” the report states.

The 14th Street bus corridor is the slowest route, and the 39, X3 and 34 were the most unreliable lines, the report states. Bus speeds averaged about 9.5 miles per hour in May, below an 11 miles per hour goal, according to the report.

Metrobus ridership has declined by 12 percent over the past five years, according to the report. The report states that operational improvements, like designating more bus-only lanes or permitting all-door boarding, would encourage more D.C. residents to use the Metrobus instead of rideshare services.

Of the District’s two miles of bus-only lanes, 1.4 miles are only designated bus lanes for the summer. The District plans to implement 25 miles of bus lanes by the 2020s, according to the report.