The issue is that the numbers are being written as strings or characters, second column onward. So it's not able to print it. Either of these two fixes will work.

1. Account for white spaces:

my @frame_stats = split(/,\s+/,$line);
[download]

2. Use "write_number":

$worksheet[$k]->write_number($frm_num, $col, $el);
[download]

Thanks a bunch for all your help!!