Others have pointed out how to do the I/O and regexp more efficiently. I'm going to stick with the structure:

DATA is a horrible name to use a file handle because perl provides a semi-magic one with the same name. When I glanced and saw that, I immediately looked for a __DATA__ marker.

I don't like big "if" blocks with no else. I think something like  next unless ( $line =~ m/..../ ); is easier to read.

Also, the formatting could be better. Four closing bracers on the same line make me think of the worst abuses in LISP.

- doug