diff --git a/Data/PAR_POPC-test.dat b/Data/PAR_POPC-test.dat
index 84ee0f5..1695686 100644
--- a/Data/PAR_POPC-test.dat
+++ b/Data/PAR_POPC-test.dat
@@ -9,6 +9,8 @@ BINNING:				10
 ERROR(0..1):			1
 PLOT(0-1):				0
 
+#                   f = fixed
+#                   - = free
 Name	In.value 	(f/-)	prior	low & high limits
 
 Norm		1e5		f		-		1e-2	1e+5		#	Normalization