diff --git a/src/timesfm/timesfm_base.py b/src/timesfm/timesfm_base.py
index 9e2c0ec..088cfab 100644
--- a/src/timesfm/timesfm_base.py
+++ b/src/timesfm/timesfm_base.py
@@ -50,13 +50,13 @@ def moving_average(arr, window_size):
 def freq_map(freq: str):
   """Returns the frequency map for the given frequency string."""
   freq = str.upper(freq)
-  if (freq.endswith("H") or freq.endswith("T") or freq.endswith("MIN") or
-      freq.endswith("D") or freq.endswith("B") or freq.endswith("U") or
-      freq.endswith("S")):
+  if freq.endswith("MS"):
+    return 1
+  elif freq.endswith(("H", "T", "MIN", "D", "B", "U", "S")):
     return 0
-  elif freq.endswith(("W", "M", "MS")):
+  elif freq.endswith(("W", "M")):
     return 1
-  elif freq.endswith("Y") or freq.endswith("Q") or freq.endswith("A"):
+  elif freq.endswith(("Y", "Q", "A")):
     return 2
   else:
     raise ValueError(f"Invalid frequency: {freq}")