diff --git a/krippendorff/krippendorff.py b/krippendorff/krippendorff.py
index 0f9b46b..f2db58f 100644
--- a/krippendorff/krippendorff.py
+++ b/krippendorff/krippendorff.py
@@ -13,7 +13,7 @@
 import numpy as np
 import numpy.typing as npt
 
-DEFAULT_DTYPE = np.float_
+DEFAULT_DTYPE = np.float64
 
 
 ValueScalarType = TypeVar("ValueScalarType", bound=np.generic)
diff --git a/pyproject.toml b/pyproject.toml
index a69f1f6..c5be136 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -28,7 +28,7 @@ classifiers = [
 
 [tool.poetry.dependencies]
 python = "^3.9,<3.13"  # Specify an upper limit, otherwise newer NumPy versions can't be installed.
-numpy = "^1.21"  # For NumPy Typing.
+numpy = ">=1.21"  # For NumPy Typing.
 
 [tool.poetry.group.test]
 optional = true