With a necessary correction 
#!/usr/bin/perl
use strict;
use warnings;
use Date::Simple qw/ today /;

my $today = today;
my $wk_before = $today - 8;
for ($today, $wk_before) {
    $_ = $_->strftime('%Y%m%d');    
}

while (<DATA>) {
    print if $_ ge $wk_before && $_ lt $today;
}

__DATA__
20110801-23:42:01,4
20110802-23:42:01,4
20110802-23:45:01,3
20110802-23:48:01,1
20110802-23:51:01,1
20110802-23:54:01,2
20110802-23:57:01,3
20110803-00:00:01,3
20110810-23:42:01,4

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In reply to Re^2: Extract data based on dates and place in new file by Anonymous Monk
in thread Extract data based on dates and place in new file by dtbach

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