Transit Center has released its National Ridership Map and graphs. See the press release at http://transitcenter.org/2017/12/18/a-new-ridership-map-to-explore-transit-trends-locally, and find the data at https://transitcenter.github.io/ridership/.

On the map page, select Sacramento-Roseville-Arden-Arcade from the upper right drop-down. The data is for the metropolitan statistical area (MSA), which is basically the SACOG region, not specifically for SacRT, though as the largest transit agency in the region, SacRT heavily influences the data.

The upper right graph starts out showing total ridership, with the steep decline in 2010 and 2011, when SacRT sharply cut routes, but there was also a strong economic downturn. Another variable can be plotted against ridership, for example, fare. Though there is a significant inverse correlation, this does not necessarily indicate cause and effect, and the fare increase starts after the ridership decline has already started. It would probably take a much more refined analysis to parse out cause and effect, but the graphs are certainly intriguing. The ridership data is yearly, to match the demographic data, but cause and effect probably needs monthly data. Note that the graphs do not have a zero baseline, so trends appear more dramatic than they actually are.

The lower right graph is fixed, and shows rail ridership, bus ridership, population change, and employment change.

The left map initially shows population density, perhaps one of the most important measures since transit requires a moderate level of density to function. A variety of demographic variables can be selected. No overlay is available.

What questions does the data raise in your mind?

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