Due to the current gap in continued funding from the U.S. National Science Foundation (NSF), the NSF Unidata Program Center has temporarily paused most operations. See NSF Unidata Pause in Most Operations for details.

Number of US versus non-US countries represented for website registration data: Apr 1 2010 to Mar 31 2011

Undetermined/misc data = unable to ascertain country information from user-provided data or email addresses.
Note: The chart above is interactive - click on the pie pieces to see the data.