Between 1874 and 2011, only 78 protected bike lanes existed nationwide. By winter 2016, 270 protected lanes were on the ground across the country, and the number keeps rising.
For the latest figures, view this inventory of protected bike lanes currently in North America. (The file is hosted in Google Drive.) All users can download the file in order to sort the data according to their needs by fields such as year built, location, length of lane, and the type of protection offered by the lane. The inventory is updated regularly with new information on protected lanes.
The graphic below is based on figures from late summer 2014.