(CBS Local) — It’s not your imagination: it really is taking longer to get to work than it used to.

According to a five-year study by the U.S. Census Bureau, the average travel times for daily commuters across America are getting longer each year. The bureau’s American Community Survey studied the average commute for the nation’s 3,142 counties from 2012 to 2016.

While the study found traveling to work is taking longer all over, workers in major metropolitan areas have been hit the hardest by the increasing delays. The census found that workers in Pennsylvania have been most affected by the national traffic jam. The state’s East Stroudsburg metro area had the longest one-way commute with 38.6 minutes of travel time. Commuters in Philadelphia have seen their trek to work go from 28.8 minutes in 2009 to 31.5 minutes in 2016.

People traveling into the New York City (35.9 minutes) and Washington D.C. (34.4 minutes) metro areas also topped the bureau’s list of longest commutes in the country. The nation’s shortest commute to work was found in Walla Walla, Washington. It took only 15 minutes to get to work in the city of 32,000 people last year.

“These estimates help people, businesses and governments throughout the country better understand the needs of their populations, the markets in which they operate and the challenges and opportunities they face,” said David Waddington, chief of the Social, Economic, and Housing Statistics Division.

While the study did not point to a direct cause for the longer trips, previous studies noted the growing number of people moving to suburban communities outside of the major city centers.

In New York City, where the census says 31 percent of workers use mass transit to commute, subway delays have reportedly tripled since 2012. New York trains were suffering more than 67,000 delays each month in 2017.