diff --git a/rowers/tests/test_unit_tests.py b/rowers/tests/test_unit_tests.py
index 467267e9..6b20a563 100644
--- a/rowers/tests/test_unit_tests.py
+++ b/rowers/tests/test_unit_tests.py
@@ -673,7 +673,8 @@ class InteractivePlotTests(TestCase):
         self.assertFalse(len(div)==0)
 
     def test_interactive_boxchart(self):
-        df = pd.read_csv('rowers/tests/testdata/boxplotdata.csv')
+        df = pl.read_csv('rowers/tests/testdata/boxplotdata.csv')
+        df = df.with_columns(pl.col("date").apply(lambda x:datetime.datetime.strptime(x, "%Y-%m-%d")))
 
         script, div = interactiveplots.interactive_boxchart(df, 'spm')
 
diff --git a/rowers/tests/testdata/testdata.tcx.gz b/rowers/tests/testdata/testdata.tcx.gz
index 0873ae7a..ac4ffb0c 100644
Binary files a/rowers/tests/testdata/testdata.tcx.gz and b/rowers/tests/testdata/testdata.tcx.gz differ