diff --git a/include/avif/avif.h b/include/avif/avif.h
index 5bc62f1a7b..1b8267f268 100644
--- a/include/avif/avif.h
+++ b/include/avif/avif.h
@@ -400,8 +400,8 @@ enum
     AVIF_MATRIX_COEFFICIENTS_CHROMA_DERIVED_CL = 13,
     AVIF_MATRIX_COEFFICIENTS_ICTCP = 14,
 #if defined(AVIF_ENABLE_EXPERIMENTAL_YCGCO_R)
-    AVIF_MATRIX_COEFFICIENTS_YCGCO_RE = 15,
-    AVIF_MATRIX_COEFFICIENTS_YCGCO_RO = 16,
+    AVIF_MATRIX_COEFFICIENTS_YCGCO_RE = 16,
+    AVIF_MATRIX_COEFFICIENTS_YCGCO_RO = 17,
 #endif
     AVIF_MATRIX_COEFFICIENTS_LAST
 };