Good start. You will need to be able to match month names (jan, feb, etc) to month numbers in your dates. You can simplify that by filling the 0th position in the array with a dummy value. Then the month number will equal the index into the array.

Next you need to design the data structure to hold your report. Here's an idea: a hash keyed by the customer name containing a reference to an array of sales by month.

use strict;
use warnings;
use Data::Dumper;

my @months = qw/dummy jan feb mar apr may jun jul aug sep oct nov dec/
+;
my (%report,$cust,$value,$date);

while (<DATA>) {
  chomp;
  if (/^[A-Z]/) {
    $cust = $_;
    next;
  }
  ($date, $value) = split ' ',$_;
  my ($mon, $year) = split '/',$date;
  $report{$cust}[$mon] = $value;
}
print Dumper(\%report);

__DATA__
CUSTA
1/2015 100
10/2015 1,000
12/2015 1,000
CUSTB
2/2015 100
10/2015 1,000
12/2015 100

[download]

This is incomplete, of course. For instance, I'm ignoring the year values in your data.

But God demonstrates His own love toward us, in that while we were yet sinners, Christ died for us. Romans 5:8 (NASB)

In reply to Re: Reformat RAW Excel Data by GotToBTru
in thread Reformat RAW Excel Data by techjohnny

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