Section 6,4: FORTRAN

 The Fortran character set includes the entire FORTRAN-77 Standard
 set plus the lowercase letters a through z (uppercase and lowercase
 letters are equivalent) and the following special characters:

    !    (exclamation mark)     <Tab> (tab)
    "    (quotation mark)       <     (left angle bracket)
    %    (percent sign)         >     (right angle bracket)
    &    (ampersand)            _     (underscore)

 All printable characters (those in the range 20(hex) through
 7E(hex), or A1(hex) through FE(hex)) can appear in comments,
 character constants, and Hollerith constants.