May is Bike Month, and the Des Moines Bicycle Collective again is sponsoring a bicycle commuting challenge for local workplaces and workers. Last year, 729 riders enrolled in the challenge, representing 323 employers. The competition is based on a formula of days in which a bike was used for all or part of a commute to work, as a factor of the number of employees participating and the size of the company. Last year, RDG Planning & Design won in its company category with a 6.33 percent commute rate. Click here for information or to register. Or you can read a Business Record article about using downtown bike lanes