How can you sort the values of a Hash alphabeticlly?

#!/usr/bin/perl
   
%FM = ( '91.1 '=> 'Radio City',
              '92.7' => 'Big FM',
              '93.5' => 'Red FM',
              '94.3' => 'Radio One',
              '98.3' => 'Radio Mirchi',
              '104.0' => 'Fever',
              '104.8' => 'Oye FM',
              '107.1' => 'FM Rainbow',
              '100.7' => 'FM Gold');

foreach $station (sort { $FM{$a} cmp $FM{$b} } keys %FM)
{
    print "$station is $FM{$station}.\n";
}