diff --git a/include/boost/preprocessor/iteration/iterate.hpp b/include/boost/preprocessor/iteration/iterate.hpp
index 9b140dd..7ff3d52 100644
--- a/include/boost/preprocessor/iteration/iterate.hpp
+++ b/include/boost/preprocessor/iteration/iterate.hpp
@@ -68,7 +68,7 @@
 #
 # /* BOOST_PP_RELATIVE_FLAGS */
 #
-# define BOOST_PP_RELATIVE_FLAGS(i) BOOST_PP_CAT(BOOST_PP_RELATIVE_, I)(BOOST_PP_ITERATION_FLAGS_)
+# define BOOST_PP_RELATIVE_FLAGS(i) BOOST_PP_CAT(BOOST_PP_RELATIVE_, i)(BOOST_PP_ITERATION_FLAGS_)
 #
 # /* BOOST_PP_ITERATE */
 #