diff --git a/frigate/api/review.py b/frigate/api/review.py
index 7f17c77e1..6bb2a4800 100644
--- a/frigate/api/review.py
+++ b/frigate/api/review.py
@@ -475,7 +475,7 @@ def motion_activity():
         logger.warning("No motion data found for the requested time range")
         return jsonify([])
 
-    df = df.astype(dtype={"motion": "float16"})
+    df = df.astype(dtype={"motion": "float32"})
 
     # set date as datetime index
     df["start_time"] = pd.to_datetime(df["start_time"], unit="s")
@@ -497,11 +497,13 @@ def motion_activity():
 
     for i in range(0, length, chunk):
         part = df.iloc[i : i + chunk]
-        df.iloc[i : i + chunk, 0] = (
-            (part["motion"] - part["motion"].min())
-            / (part["motion"].max() - part["motion"].min())
-            * 100
-        ).fillna(0.0)
+        min_val, max_val = part["motion"].min(), part["motion"].max()
+        if min_val != max_val:
+            df.iloc[i : i + chunk, 0] = (
+                part["motion"].sub(min_val).div(max_val - min_val).mul(100).fillna(0)
+            )
+        else:
+            df.iloc[i : i + chunk, 0] = 0.0
 
     # change types for output
     df.index = df.index.astype(int) // (10**9)