2008-08-22: Corrected input data for the background model implemented. Improved values in regions not covered by observations. Period between February and August 2008 will be reprocessed for the archive.
2007-08-13: Tabs on page are no longer images and text index page contains checkmarks for existing files.
2007-06-19: US-TEC transitioned to a fully operational product.
2007-02-16: Difference from 10 day average indicating recent trend plot color scale reduced to -30 - +30 TECU
2007-02-15: Vertical Total Electron Content plot color scale reduced to 0-50 TECU.