diff --git a/backuppc_check.pl b/backuppc_check.pl
index 8a01a6b..57b8061 100644
--- a/backuppc_check.pl
+++ b/backuppc_check.pl
@@ -85,7 +85,7 @@ print("Size Consistency : ");
 
 # TOO BIG ?
 my $toobig = "1";
-if ( $json->{new_size} > $json->{new_size_q3} + $json->{new_size_q3} - $json->{new_size_q1} * 1.5 && $json->{new_size} > $json->{new_size_avg} * 6 ) {
+if ( $json->{new_size} > ($json->{new_size_q3} + $json->{new_size_q3} - $json->{new_size_q1}) * 1.5 && $json->{new_size} > $json->{new_size_avg} * 6 ) {
   $toobig = "0";
   }
 else {
@@ -94,7 +94,7 @@ else {
 
 # TOO SMALL ?
 my $toosmall = "1";
-if ( $json->{new_size} < $json->{new_size_q1} - $json->{new_size_q3} - $json->{new_size_q1} * 1.5 && $json->{new_size} < $json->{new_size_avg} / 3 ) {
+if ( $json->{new_size} < ($json->{new_size_q1} - $json->{new_size_q3} - $json->{new_size_q1}) * 1.5 && $json->{new_size} < $json->{new_size_avg} / 3 ) {
   $toosmall = "0";
   }
 else {