According to this article, we tend to over-count drivers and under-count people who use transit. They believe that if we correctly counted all who benefit from transit, including residents, government and business … would more easily see the importance and cost-effectiveness of reliable transit options.
As stated in the City Commentary piece, “by far the most common way to measure transit use is “commute mode share,” or the percentage of workers who use transit to get to their job. For the most part, this is a measure of convenience: it’s the most direct way the Census asks about transportation, which means it’s the easiest way to get consistent data from any city or metropolitan area in the country.
“But it also has a lot of problems. For one, the vast majority of trips – about 84% – aren’t simple home-to-work commutes. And it’s not just that people who work also go to the grocery store, restaurants, or friends’ homes. Lots of people don’t work at all, and those people – largely students, the elderly, or people with disabilities – are disproportionately likely to use transit for all or almost all of their trips. Finally, plenty of people who do work might drive three or four days a week and take transit the other one or two. But since the Census only asks about what they do most of the time, they’ll show up as “drivers.” All of these things will tend to undercount a place’s reliance on public transit.”
Read the full article here.