diff --git a/labsw/__init__.py b/labsw/__init__.py
index 0da2406..52de158 100644
--- a/labsw/__init__.py
+++ b/labsw/__init__.py
@@ -1 +1 @@
-__version__ = '0.1.6.2'
+__version__ = '0.1.6.3'
diff --git a/labsw/io.py b/labsw/io.py
index 1267094..22dc6b6 100644
--- a/labsw/io.py
+++ b/labsw/io.py
@@ -44,6 +44,9 @@ def process_data_RH_logger(filepath, every):
     df['dMdt_SG'] = savgol_filter(df['m_mf'], window_length=10000, polyorder=1, deriv=1, delta=delta)
     df['dMdt_diff'] = df['m_mf'].diff(periods=1000) / df['time'].diff(periods=1000)
 
+    df['dweightdt_SG'] = savgol_filter(df['weight'], window_length=10000, polyorder=1, deriv=1, delta=delta)
+    df['dweightdt_diff'] = df['weight'].diff(periods=1000) / df['time'].diff(periods=1000)
+
     h5path = os.path.splitext(filepath)[0]
     h5path += '-processed.h5'
     df = df.iloc[::every]