Since unpack returns strings of zero length, you can check with length: 
use warnings;
use strict;
 
printf("%-11s %-27s %9s %11s","Date","Description","Incoming","Outgoin
+g\n");
my $x = 0;
my $tot;
my $totex;
while (<DATA>) {
    if ($x==0) {$x++;next;}
    my ($date,$des,$inc,$exp) = unpack("A10 A27 A10 A*", $_);
    $inc = 0 unless length $inc;
    $exp = 0 unless length $exp;
    printf("%-10s %-27s %10.2f %10.2f\n",$date,$des,$inc,$exp);
    $tot += $inc;
    $totex += $exp;
}
printf("%38s %10.2f %10.2f","Totals",$tot,$totex);
print "\n";

__DATA__
Date       Description                incoming     outgoing
01/24/2001 Zed's Camel Emporium         100.00      1147.99
01/28/2001 Flea spray                                 24.99
01/29/2001 Camel rides to tourists      235.00             
01/31/2001 avage1                       125.00                      
01/20/2001 carpe diem                    20.00        23.00

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In reply to Re: use warnings is complaining by toolic
in thread use warnings is complaining by Anonymous Monk

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