I am not sure why this doesn't work, I am wanting to insert the label Date and a \n on each line that a date appears in my test files, so that I can populate a hash to insert into a db. 
use strict;
use warnings;

my $text;

while(<DATA>) {
    chomp($_);
    if($_ =~ /\d{1,2}\/\d{1,2}\/\d{4}/) {
       unshift($text .= "Date\n" unless $. == 1);
        $text .= $_;
    } else {
        $text .= "\n,".$_;
    }
}

print $text;

__DATA__
1/3/2007 12:20:01 AM
Login,12.588309
SearchLoad,9.432586
SearchCount,20:0.196329
SearchResults,7.418672
SearchSave,3.616305
SearchDelete,2.066482
SearchDetails,6.873061
ClientAdd,0.784989
CMALoad,1.859894
CMASave,3.249620
CMADelete,0.450952
ClientDelete,0.305768
Logout,0.823402
1/3/2007 12:49:22 AM
Login,10.958312
SearchLoad,13.644527
SearchCount,41:0.483233
SearchResults,7.027840
SearchSave,4.222601
SearchDelete,0.305821
SearchDetails,7.443877
ClientAdd,1.552915
CMALoad,1.202711
CMASave,5.285398
CMADelete,0.233119
ClientDelete,0.425521
Logout,0.560862

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In reply to inserting into file by grashoper

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