diff --git a/labsw/__init__.py b/labsw/__init__.py
index f3cc595..ecf2e74 100644
--- a/labsw/__init__.py
+++ b/labsw/__init__.py
@@ -1 +1 @@
-__version__ = '0.1.6.8'
+__version__ = '0.1.6.9'
diff --git a/labsw/io.py b/labsw/io.py
index 4d4e6a8..f7ed965 100644
--- a/labsw/io.py
+++ b/labsw/io.py
@@ -46,7 +46,7 @@ def process_data_RH_logger(filepath, every, diff_period=1_000, SG_window=10_000)
     df = load_data_RH_logger(filepath, every=1)
 
     m0 = df['weight'].iloc[0]
-    mf = df['dm_m'].tail(300).mean()
+    mf = df['weight'].tail(300).mean()
     # Variation
     df['m'] = df['weight'] - m0
     df['M'] = (df['weight'] - m0) / (mf - m0)