Note that nothing is printed unless your regex is true. Obvious conclusion, your regex doesn't return true. To test that you could do one or both of the following easy things:

a) copy the regex into a test script and try to match a line it should be matching. Try to experiment with the regex and the line until you find out what is matched and how it should be changed to match the correct line.

b) insert print statements into your code to show you on the web page what the variables $start_year ... $test_site and $string contain (i.e. print "start_year=$start_year:test_site=$test_site:...\n";. The ':' is there to show you where the strings end). Compare that with what you expected the variables to contain.

PS: Please post your code using <code>-tags. The code as you posted it doesn't run without syntax errors, probably a problem of copying to this website and using the wrong tag. "my request" should be "my $request". On the second to last line the line seems to be cut off at the end. Similar the "Report for..." line is missing a ';'