diff --git a/salt/common/telegraf/scripts/oldpcap.sh b/salt/common/telegraf/scripts/oldpcap.sh
index e9ae7698a..1f1798f8a 100644
--- a/salt/common/telegraf/scripts/oldpcap.sh
+++ b/salt/common/telegraf/scripts/oldpcap.sh
@@ -3,6 +3,6 @@
 # Get the data
 OLDPCAP=$(find /nsm/pcap -type f -printf '%Cs %p\n' | sort | head -n 1 | awk {'print $1'})
 DATE=$(date +%s)
-AGE=$(expr $DATE - $OLDPCAP)
+AGE=$(($DATE - $OLDPCAP))
 
 echo "pcapage seconds=$AGE"