By way of explanation, this builds a long regexp through basic string interpolation like the following:

/^(?:1950|1951|1952|1953|...|2049|2050)$/;
[download]

After generating a regex like that, if you will be using it often, you might want to optimize it for common prefixes or suffixes.

use Regex::PreSuf;
my $re = presuf(1950..2050);
[download]