My script works this way:-

rm -f $1/$2
filepath=`/usr/bin/ls -tr $1 | /usr/bin/grep 'USSD_successrate_gt'`

if [ "$filepath" != "" ]
then
for filename in $filepath
do
cat $1/$filename | awk -f: '{print $0}' >> $1/$2
done

My input files have headers on the first row of each file which i want to remove when i am concatenating the files.

day,hour,called,status,result,operation type
2007-07-15,00,S147:T0:60120001051,0,40736,total trans/hour

What command should i include in this line

cat $1/$filename | awk -f: '{print $0}' >> $1/$2

TQ

Nimi

FYI

$1 = File directory
$2 = Output File name

Nimi

If all you want to do is remove the first row, try:
tail +2 < filename