The above chart shows the top 10 U.S. airlines by system scheduled enplaned passengers for April 2009. It also shows April 2008 numbers for comparison. As you can see most major airlines have seen substantable declines in passengers in April 2009 compared to last year.
Data source:
U.S. Bureau of Transportation Statistics, T-100.
Note: System scheduled enplanements includes domestic and international.
=================================================================================