diff --git a/inc/temp.inc.sh b/inc/temp.inc.sh
index 04156b3a..c51ce326 100644
--- a/inc/temp.inc.sh
+++ b/inc/temp.inc.sh
@@ -98,7 +98,7 @@ CHECKTEMP(){
 				for R in ${PW_TEMPIND_RANGE[@]}; do
 					lookup=($(${mysql_conn} -e "SELECT sensorid,temp FROM servermonitor.sensor_data WHERE sensorid IN (${sensorsqry}) AND date >= DATE_SUB(NOW(), INTERVAL ${R} MINUTE) AND date <= DATE_SUB(NOW(), INTERVAL $(expr ${R} - 7) MINUTE) ORDER BY date ASC LIMIT ${sq}"))
 					for i in {2..10..2}; do
-						RANGE_TEMPS["${R}-${lookup[${i}]}"]=${lookup[((${i}++))]}
+						RANGE_TEMPS["${R}-${lookup[${i}]}"]=${lookup[$(expr ${i} + 1)]}
 					done
 				done