The chart below displays the number of scenes visible to all users on EarthExplorer as of March 31, 2016.
In addition to the current Landsat 8 and Landsat 7 missions that are constantly increasing the data in the USGS archive, the Landsat Global Archive Consolidation (LGAC) effort is returning unique Landsat 1-5 MSS and TM data originally downlinked to International Ground Stations into the USGS archive, making even more data available to all users.
The files on the USGS Landsat Global Archive webpage provide a view of the data added to the USGS archive per satellite, per year.
This image, showing the northwest portion of Washington State, is representative of one of the many scenes of Path 46 Row 27 downloaded in March 2016. Snow covering Mount Rainier, the highest mountain in state of Washington, can be seen in bright light blue in the lower part of the image. The urban areas of Seattle and nearby cities can be seen in shades of gray and purple, along the shores of the Puget Sound.
Landsat 8 Path 46 Row 27
Acquired September 11, 2015
The Landsat archive became available to all users at no charge in December of 2008. As of March 31, 2016, over 37 million scenes have been downloaded by users worldwide.
This graph shows the top ten Landsat data uses from October 1, 2015 through March 31, 2016.