diff --git a/marginaleffects/datagrid.py b/marginaleffects/datagrid.py
index 0b29759..6fea645 100644
--- a/marginaleffects/datagrid.py
+++ b/marginaleffects/datagrid.py
@@ -132,7 +132,8 @@ def datagridcf(model=None, newdata=None, **kwargs):
     result = newdata.join(df_cross, how = "cross")
 
     # Create rowid and rowidcf
-    result = result.with_columns(pl.Series(range(result.shape[0])).alias("rowidcf"))
+    rowidcf = [i for i in range(newdata.shape[0]) for _ in range(result.select(pl.count()).item() // newdata.select(pl.count()).item())]
+    result = result.with_columns(pl.Series(rowidcf).alias("rowidcf"))
 
     result.datagrid_explicit = list(kwargs.keys())
 
diff --git a/tests/test_datagrid.py b/tests/test_datagrid.py
index 9559900..c25b31e 100644
--- a/tests/test_datagrid.py
+++ b/tests/test_datagrid.py
@@ -19,3 +19,4 @@ def test_simple_grid():
 def test_cf():
     assert datagrid(newdata = mtcars, mpg = 32).shape[0] == 1
     assert datagridcf(newdata = mtcars, mpg = [30, 32]).shape[0] == 64
+    assert datagridcf(newdata = mtcars, mpg = [30, 32]).unique("rowidcf").shape[0] == 32
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