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Summary
PNG version of [1] from [2]archive copy at the Wayback Machine, a prettified version of [3] from [4]. Not sure which years this graph is based on - neither page lists them.
PNG version of [http://www.nhc.noaa.gov/gifs/peakofseason.gif] from [http://www.nhc.noaa.gov/pastprofile.shtml], a prettified version of [http://hurricanes.noaa.gov/prepare/images/season.gif] from [http://hurricanes.noaa.gov/prepare/season.htm]. Not sure
File usage
The following pages on the English Wikipedia use this file (pages on other projects are not listed):