diff --git a/CHANGELOG.md b/CHANGELOG.md
new file mode 100644
index 0000000..0c4b6ff
--- /dev/null
+++ b/CHANGELOG.md
@@ -0,0 +1,16 @@
+# Changelog
+
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
+and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## [0.1.1] - 2022-01-19
+
+### Fixed
+
+- Fixed `MAIC.compare_populations` bug [[#1](https://github.com/AidanCooper/indcomp/issues/1)]
+
+## [0.1.0] - 2022-01-17
+
+Initial alpha release
\ No newline at end of file
diff --git a/indcomp/__init__.py b/indcomp/__init__.py
index de1528a..7401508 100644
--- a/indcomp/__init__.py
+++ b/indcomp/__init__.py
@@ -8,6 +8,6 @@
  - Simulated Treatment Comparison (STC)
 """
 
-__version__ = "0.1.0"
+__version__ = "0.1.1"
 
 from ._maic import MAIC
diff --git a/indcomp/_maic.py b/indcomp/_maic.py
index 8a28c92..c25c111 100644
--- a/indcomp/_maic.py
+++ b/indcomp/_maic.py
@@ -174,12 +174,18 @@ def compare_populations(
             raise e.NoWeightsException()
 
         # create grid
-        ncols = min(ncols, len(variables))
-        nrows = len(variables) // ncols
-        remainder = len(variables) % ncols
+        if len(variables) == 1:
+            ncols, nrows, remainder = 1, 1, 0
+        else:
+            ncols = min(ncols, len(variables))
+            nrows = len(variables) // ncols
+            remainder = len(variables) % ncols
         fig, axes = plt.subplots(nrows, ncols, figsize=(ncols * 4, nrows * 4))
         fig.patch.set_facecolor("white")
-        axes = axes.flatten()
+        if len(variables) == 1:
+            axes = [axes]
+        else:
+            axes = axes.flatten()
         for r in range(1, remainder + 1):
             axes[-r].axis("off")
 
diff --git a/setup.py b/setup.py
index 4a6bd2e..2f3be3f 100644
--- a/setup.py
+++ b/setup.py
@@ -6,7 +6,7 @@
 
 setup(
     name="indcomp",
-    version="0.1.0",
+    version="0.1.1",
     description="Perform indirect treatment comparison (ITC) analyses",
     long_description=README,
     long_description_content_type="text/markdown",
diff --git a/tests/test_maic.py b/tests/test_maic.py
index 7884cea..410416b 100644
--- a/tests/test_maic.py
+++ b/tests/test_maic.py
@@ -19,14 +19,19 @@ def data_NICE_DSU18():
     return (df_ind, df_tar)
 
 
-@pytest.fixture
-def correct_config_maic(data_NICE_DSU18):
+@pytest.fixture(
+    params=[
+        {"age.mean": ("mean", "age")},
+        {"age.mean": ("mean", "age"), "age.sd": ("std", "age", "age.mean")},
+    ]
+)
+def correct_config_maic(request, data_NICE_DSU18):
     """Return a correctly configued MAIC instance"""
     df_ind, df_tar = data_NICE_DSU18
     return MAIC(
         df_ind,
         df_tar,
-        {"age.mean": ("mean", "age"), "age.sd": ("std", "age", "age.mean")},
+        request.param,
     )
 
 
@@ -123,7 +128,9 @@ def test_maic_methods(correct_config_maic):
     # calculate_weights
     with optional_step("calculate_weights") as calculate_weights:
         maic.calc_weights()
-        assert np.isclose(maic.ESS_, 178.56, atol=0.01)
+        assert np.isclose(maic.ESS_, 178.56, atol=0.01) or np.isclose(
+            maic.ESS_, 188.89, atol=0.01
+        )
     yield calculate_weights
 
     # plot_weights