Aggregate travel time to work is calculated by adding all of the travel times (in minutes) for workers who did not work at home. Aggregate travel times of workers having specific characteristics also are computed. The aggregate travel time is subject to rounding, which means that all cells in a matrix are rounded to the nearest 5 minutes. (For more information, see "Aggregate" under "Derived Measures.")
Social Explorer; U.S. Census Bureau; 2016 ACS 1-year and 2012-2016 ACS 5-year Data Releases: Technical Documentation.