$text= "Average of column 3 for the last " ;
             #, scalar (@lines)," days: $average\n";

##</code><code>##

$text = "Average of column 3 for the last " .
              scalar(@lines) . " days: $average\n";

##</code><code>##

$text = join '', "Average of column 3 for the last ",
                       scalar(@lines), " days: $average\n";

##</code><code>##

my $last = (split /:/, $lines[-1])[3];

##</code><code>##

my @tmp = split /:/, $lines[-1];
my $last = $tmp[3];