diff --git a/GRIB2_CodeFlag_4_2_10_4_CodeTable_en.csv b/GRIB2_CodeFlag_4_2_10_4_CodeTable_en.csv
index d656e0e..6187cc0 100644
--- a/GRIB2_CodeFlag_4_2_10_4_CodeTable_en.csv
+++ b/GRIB2_CodeFlag_4_2_10_4_CodeTable_en.csv
@@ -49,6 +49,7 @@ Parameter number by product discipline and parameter category,"Product disciplin
 Parameter number by product discipline and parameter category,"Product discipline 10 - Oceanographic products, parameter category 4: subsurface properties",49,,Sea water column integrated zonal mass transport,,,kg m-1 s-1,Operational
 Parameter number by product discipline and parameter category,"Product discipline 10 - Oceanographic products, parameter category 4: subsurface properties",50,,Sea water column integrated practical salinity,,,g kg-1 m,Operational
 Parameter number by product discipline and parameter category,"Product discipline 10 - Oceanographic products, parameter category 4: subsurface properties",51,,Sea water column integrated salinity,,,kg kg-1 m,Operational
-Parameter number by product discipline and parameter category,"Product discipline 10 - Oceanographic products, parameter category 4: subsurface properties",52-191,,Reserved,,,,Operational
+Parameter number by product discipline and parameter category,"Product discipline 10 - Oceanographic products, parameter category 4: subsurface properties",52,,Mixed layer depth,,,m,Operational
+Parameter number by product discipline and parameter category,"Product discipline 10 - Oceanographic products, parameter category 4: subsurface properties",53-191,,Reserved,,,,Operational
 Parameter number by product discipline and parameter category,"Product discipline 10 - Oceanographic products, parameter category 4: subsurface properties",192-254,,Reserved for local use,,,,Operational
 Parameter number by product discipline and parameter category,"Product discipline 10 - Oceanographic products, parameter category 4: subsurface properties",255,,Missing,,,,Operational