DateTime would be a better module to use than localtime,

use DateTime;

my $dt = DateTime->now();

print "Current Month " . $dt->month_name . "\n";

$dt->subtract( months => 1 );
print "Last Month " . $dt->month_name . "\n";

$dt->subtract( months => 1 );
print "2 Months ago " . $dt->month_name . "\n";

$dt->subtract( months => 1 );
print "3 Months ago " . $dt->month_name . "\n";
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