diff --git a/bin/tests/system/statistics/tests.sh b/bin/tests/system/statistics/tests.sh
index f1cdf48f1f..3dc04099c4 100644
--- a/bin/tests/system/statistics/tests.sh
+++ b/bin/tests/system/statistics/tests.sh
@@ -71,7 +71,7 @@ $RNDCCMD -s 10.53.0.3 stats > /dev/null 2>&1
 [ -f ns3/named.stats ] || ret=1
 [ "$CYGWIN" ] || \
 nsock0nstat=`grep "UDP/IPv4 sockets active" ns3/named.stats | awk '{print $1}'`
-[ 0 -ne ${nsock0nstat:0} ] || ret=1
+[ 0 -ne ${nsock0nstat:-0} ] || ret=1
 if [ $ret != 0 ]; then echo_i "failed"; fi
 status=`expr $status + $ret`
 n=`expr $n + 1`