diff --git a/pandas/tests/groupby/test_allowlist.py b/pandas/tests/groupby/test_allowlist.py
index d495441593aed..d16e8ef56a42c 100644
--- a/pandas/tests/groupby/test_allowlist.py
+++ b/pandas/tests/groupby/test_allowlist.py
@@ -3,38 +3,72 @@
 Do not add tests here!
 """
 
+from string import ascii_lowercase
+
+import numpy as np
 import pytest
 
 from pandas import (
     DataFrame,
+    Series,
     date_range,
 )
 import pandas._testing as tm
 
+AGG_FUNCTIONS = [
+    "sum",
+    "prod",
+    "min",
+    "max",
+    "median",
+    "mean",
+    "skew",
+    "std",
+    "var",
+    "sem",
+]
+AGG_FUNCTIONS_WITH_SKIPNA = ["skew"]
+
+
+@pytest.fixture
+def df():
+    return DataFrame(
+        {
+            "A": ["foo", "bar", "foo", "bar", "foo", "bar", "foo", "foo"],
+            "B": ["one", "one", "two", "three", "two", "two", "one", "three"],
+            "C": np.random.randn(8),
+            "D": np.random.randn(8),
+        }
+    )
 
-@pytest.mark.parametrize(
-    "op",
-    [
-        "sum",
-        "prod",
-        "min",
-        "max",
-        "median",
-        "mean",
-        "skew",
-        "std",
-        "var",
-        "sem",
-    ],
-)
+
+@pytest.fixture
+def df_letters():
+    letters = np.array(list(ascii_lowercase))
+    N = 10
+    random_letters = letters.take(np.random.randint(0, 26, N))
+    df = DataFrame(
+        {
+            "floats": N / 10 * Series(np.random.random(N)),
+            "letters": Series(random_letters),
+        }
+    )
+    return df
+
+
+@pytest.fixture
+def raw_frame():
+    return DataFrame([0])
+
+
+@pytest.mark.parametrize("op", AGG_FUNCTIONS)
 @pytest.mark.parametrize("axis", [0, 1])
 @pytest.mark.parametrize("skipna", [True, False])
 @pytest.mark.parametrize("sort", [True, False])
-def test_regression_allowlist_methods(op, axis, skipna, sort):
+def test_regression_allowlist_methods(raw_frame, op, axis, skipna, sort):
     # GH6944
     # GH 17537
     # explicitly test the allowlist methods
-    raw_frame = DataFrame([0])
     if axis == 0:
         frame = raw_frame
         msg = "The 'axis' keyword in DataFrame.groupby is deprecated and will be"
@@ -45,8 +79,7 @@ def test_regression_allowlist_methods(op, axis, skipna, sort):
     with tm.assert_produces_warning(FutureWarning, match=msg):
         grouped = frame.groupby(level=0, axis=axis, sort=sort)
 
-    if op == "skew":
-        # skew has skipna
+    if op in AGG_FUNCTIONS_WITH_SKIPNA:
         result = getattr(grouped, op)(skipna=skipna)
         expected = frame.groupby(level=0).apply(
             lambda h: getattr(h, op)(axis=axis, skipna=skipna)
@@ -121,4 +154,4 @@ def test_groupby_selection_other_methods(df):
 
     tm.assert_frame_equal(
         g.filter(lambda x: len(x) == 3), g_exp.filter(lambda x: len(x) == 3)
-    )
+    )
\ No newline at end of file