One way: 
use warnings;
use strict;
use List::Util qw(sum);

my @pe_total = (
    {
    'COMP_TOTAL' => '2445.00'
    },
    {
    'COMP_TOTAL' => '728.00'
    }
);

print sum(map { $_->{COMP_TOTAL} } @pe_total), "\n";

__END__

3173

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See also:

In reply to Re: Sum of values in an array by toolic
in thread Sum of values in an array by Anonymous Monk

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