diff --git a/docs/conf.py b/docs/conf.py
index 6fc3527a..b9e924be 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -38,7 +38,6 @@
 
 
 html_theme = "sphinx_rtd_theme"
-html_theme_path = [sphinx_rtd_theme.get_html_theme_path()]
 
 
 # -- General configuration ------------------------------------------------
diff --git a/docs/requirements.txt b/docs/requirements.txt
index ea20c457..2b13b11f 100644
--- a/docs/requirements.txt
+++ b/docs/requirements.txt
@@ -1,7 +1,7 @@
 # File: docs/requirements.txt
 
-sphinx>=7.0.0
-sphinx_rtd_theme>=1.0.0
+sphinx>=8.0.0
+sphinx_rtd_theme>=3.0.0
 readthedocs-sphinx-search>=0.3.2
 jinja2>=3.0.0
 mock
diff --git a/docs/whats_new.rst b/docs/whats_new.rst
index db915f65..2dc253b5 100644
--- a/docs/whats_new.rst
+++ b/docs/whats_new.rst
@@ -29,6 +29,7 @@ Internal Changes
   - Ensure proper shape of inputs when loading external data.
 
 - Avoid :py:class:`DeprecationWarning` raised in `invert_matrix`` test.
+- Remove `get_html_theme_path` from docs conf.
 
 v3.14.1 (2024/07/18)
 --------------------
diff --git a/pysd/py_backend/external.py b/pysd/py_backend/external.py
index 61e80419..ae7ee0cd 100644
--- a/pysd/py_backend/external.py
+++ b/pysd/py_backend/external.py
@@ -977,11 +977,12 @@ def _initialize(self):
         if len(self.coords) > 0:
             reshape_dims = tuple(utils.compute_shape(self.coords))
             data = self._reshape(data, reshape_dims)
-            data = xr.DataArray(
+            return xr.DataArray(
                 data=data, coords=self.coords, dims=list(self.coords)
             )
-
-        return data
+        else:
+            # need to ensure float is returned and not numpy.float
+            return float(data)
 
     def _get_constant_data(self, data_across, cell, shape):
         """