diff --git a/check_opnsense_traffic_for_host.py b/check_opnsense_traffic_for_host.py
index 3164d47..f319fe3 100755
--- a/check_opnsense_traffic_for_host.py
+++ b/check_opnsense_traffic_for_host.py
@@ -120,11 +120,11 @@ def main():
             ok.append(name)
             status = '[OK]'
 
-        perf_data.append(f'\'{name}RateIn\'={int(data["rate_in"])}B;{warn_value};{crit_value};0;')
-        perf_data.append(f'\'{name}RateOut\'={int(data["rate_out"])}B;{warn_value};{crit_value};0;')
-        perf_data.append(f'\'{name}CumulativeIn\'={int(data["cumulative_in"])}B;{warn_value};{crit_value};0;')
-        perf_data.append(f'\'{name}CumulativeOut\'={int(data["cumulative_out"])}B;{warn_value};{crit_value};0;')
-        perf_data.append(f'\'{name}Connections\'={int(data["connections"])}B;{warn_value};{crit_value};0;')
+        perf_data.append(f'\'{name}_rate_in\'={int(data["rate_in"])}B;{warn_value};{crit_value};0;')
+        perf_data.append(f'\'{name}_rate_out\'={int(data["rate_out"])}B;{warn_value};{crit_value};0;')
+        perf_data.append(f'\'{name}_cumulative_in\'={int(data["cumulative_in"])}B;{warn_value};{crit_value};0;')
+        perf_data.append(f'\'{name}_cumulative_out\'={int(data["cumulative_out"])}B;{warn_value};{crit_value};0;')
+        perf_data.append(f'\'{name}_connections\'={int(data["connections"])}B;{warn_value};{crit_value};0;')
 
         output_table = [
             ('Host', 'Interface', 'Rate In', 'Rate Out', 'Cumulative In', 'Cumulative Out', 'Connections', 'Status'),