diff --git a/include/openmc/tallies/filter.h b/include/openmc/tallies/filter.h
index 104a55e473..47b4c8a94a 100644
--- a/include/openmc/tallies/filter.h
+++ b/include/openmc/tallies/filter.h
@@ -18,7 +18,7 @@
 namespace openmc {
 
 enum class FilterType {
-  AZIMUTHAL = 0,
+  AZIMUTHAL,
   CELLBORN,
   CELLFROM,
   CELL,