The City of Chicago released the results of bike counts conducted at 26 locations around the city in the summer and fall of 2009.  The counts were made with automated pneumatic tube counters designed specifically to count bicycles but not motorized vehicles.  Counts were taken for 24 hours on Tuesdays, Wednesdays, and Thursdays in warmer-weather conditions.  All but two of the count locations have on-street bikeway markings (bike lane, marked shared lane, or bus/bike lane).

Comparing the bike counts to 2006 vehicle counts shows that in some locations bicycles constitute a significant percent of roadway traffic (i.e. bicycles in relation to motor vehicles) – as high as 21.9 percent (at 640 N. Milwaukee Ave. in September).

Seventeen of the 26 count locations recorded more than 200 daily cyclists, with the highest count (again, at 640 N. Milwaukee Ave.) being 3,121 cyclists.