String math help needed

#!/usr/bin/ksh
#LOGFILE=/var/opt/ixos/log/notification_warning.log 
#DAT1=/var/opt/ixos/monitor/percentages.dat 
#DAT2=/var/opt/ixos/monitor/mountpoints.dat 
THRESHOLD=75 
#`rm $DAT1` 
#`rm $DAT2` 
`bdf | grep /var/opt/ixos | awk '{ print $4 }' | cut -f1 -d"%" > test.dat` `bdf | grep /var/opt/ixos | awk '{ print $5 }' > test2.dat` 
set -A PERCENTAGES `cat test.dat` 
set -A MOUNTPOINTS `cat test2.dat`  
len=${#PERCENTAGES[*]} 
i=0 
while [ $i -lt $len ] do         
     value=${PERCENTAGES[$i]}         
     if ( $value > $THRESHOLD ) then
                    echo "${MOUNTPOINTS[$i]} IS ${PERCENTAGES[$i]}% FULL RIGHT NOW....please increase the space soon."         
     fi         
     (( i=i+1 )) 
done  
exit 0

The above is working just fine for me except that the $value > $THRESHOLD comparison fails. PERCENTAGES is simply an array of numbers (actually strings) that I want to cue off of and only write a line to a log file if the value is above whatever THRESHOLD is set to. Sounds easy enough but apparently shell script math and I don't get along.

Any help is appreciated.

Try to substitute this:

if ( $value > $THRESHOLD ) then

with this:

if [ $value -gt $THRESHOLD ] then