my $state = $hash{$date}++ ? 'exists' : "doesn't exist";
print qq(<TD class="table_font">$date - Hash $state</TD>\n);

##</code><code>##

if ($hash{$date}++) {
  print qq(<TD class="table_font">$date - Hash exists</TD>\n);
}
else {
  print qq(<TD class="table_font">$date - Hash doesn't exist</TD>\n);
}