diff --git a/modern_7_timeseries.ipynb b/modern_7_timeseries.ipynb
index 051b05c..1a3b844 100644
--- a/modern_7_timeseries.ipynb
+++ b/modern_7_timeseries.ipynb
@@ -1064,7 +1064,7 @@
    "source": [
     "### Holiday Calendars\n",
     "\n",
-    "There are a whole bunch of special calendars, useful for traders probabaly."
+    "There are a whole bunch of special calendars, useful for traders probably."
    ]
   },
   {