diff --git a/rowers/dataprep.py b/rowers/dataprep.py
index 9744b6b9..b6dbad35 100644
--- a/rowers/dataprep.py
+++ b/rowers/dataprep.py
@@ -518,7 +518,7 @@ def dataprep(rowdatadf,id=0,bands=True,barchart=True,otwpower=True,
     try:
         drivespeed = drivelength/rowdatadf[' DriveTime (ms)']*1.0e3
     except TypeError:
-        drivespeed = 0.0*rowdatadf['TimeStam (sec)']
+        drivespeed = 0.0*rowdatadf['TimeStamp (sec)']
         
     drivespeed = drivespeed.fillna(value=0)
     driveenergy = drivelength*averageforce*4.44822