diff --git a/asv_bench/benchmarks/categoricals.py b/asv_bench/benchmarks/categoricals.py
index b30ad9f7b4905..ff0b3b2fb651d 100644
--- a/asv_bench/benchmarks/categoricals.py
+++ b/asv_bench/benchmarks/categoricals.py
@@ -187,7 +187,7 @@ def time_remove_categories(self):
 class Rank:
     def setup(self):
         N = 10**5
-        ncats = 20
+        ncats = 15
 
         self.s_str = pd.Series(tm.makeCategoricalIndex(N, ncats)).astype(str)
         self.s_str_cat = pd.Series(self.s_str, dtype="category")