#!/usr/bin/perl -w
use strict;

my @rows=<DATA>;

my $val=0;
   for (@rows) {
     chomp;
     if (/([\d.]+)/) {
       $val += $1;
       $val= sprintf( "%6.2f", $val);
       warn "Added $1 from $_ and set it to $val\n";
     }
   }

__DATA__
we get to $6257.65
now we add $33.4099999999999999
we add $37.24