"Nationwide, the number of people who traveled to work by bike increased roughly 60 percent over the last decade, from about 488,000 in 2000 to about 786,000 during the 2008-2012 period. This is the largest percentage increase of all commuting modes tracked by the 2000 Census and the 2008-2012 American Community Survey," according to a press release announcing the United States Census Bureau's new report, titled "Modes Less Traveled—Bicycling and Walking to Work in the United States: 2008–2012."
Moreover, "[while] bicyclists still account for just 0.6 percent of all commuters, some of the nation's largest cities have more than doubled their rates since 2000. Portland, Ore., had the highest bicycle-commuting rate at 6.1 percent, up from 1.8 percent in 2000. In Minneapolis, the rate increased from 1.9 percent to 4.1 percent."
The results for walking, however, held steady: "After steadily decreasing since 1980, the percent of people who walk to work has stabilized since 2000. In 1980, 5.6 percent of workers walked to work, and that rate declined to 2.9 percent by 2000. However, in the 2008-2012 period, the rate of walkers remained statistically unchanged from 2000."
On the same day as the study, the Census also released a new commuting edition of the interactive map Census Explorer. Planetizen blogger Michael Lewyn already crunched that data about average commute times in cities and suburbs around the country.
Michael Stenzel has also analyzed some of the data in the report, especially with regard to the growing rate of walking and biking to work in Chicago: "In Chicago in 2000, 5.7% of workers walked to work, but by 2012, the percent had increased to 6.4%," and "in 2000, only half a percent of Chicagoans rode their bikes to work, but by 2012, it was 1.3%."