Per capita annual visitation rates for U.S. libraries

Source

I quote from the report.

Nationwide, per capita visitation increased every year during the study period, growing steadily from 4.13 in 1997 to 4.91 in 2007, an increase of 19 percent.

 The availability of Internet terminals in public libraries rose sharply between 2000 and 2007, increasing by 90 percent on a per capita basis. This dramatic increase is one example of the way U.S. public libraries are expanding their range of services to meet patron demand.