diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 215d2062..f4a5b842 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -10,7 +10,7 @@ repos:
     args: [--py36-plus]
 
 - repo: https://github.com/psf/black
-  rev: 21.12b0
+  rev: 22.1.0
   hooks:
   - id: black-jupyter
 
diff --git a/tests/decay/test_decay.py b/tests/decay/test_decay.py
index 992efc9b..4147be77 100644
--- a/tests/decay/test_decay.py
+++ b/tests/decay/test_decay.py
@@ -302,7 +302,7 @@ def test_DecayChain_flatten_complex():
     assert dc_flatten.decays[dc_flatten.mother].daughters == DaughtersDict(
         {"gamma": 6, "pi+": 3, "pi-": 2}
     )
-    assert dc_flatten.bf == approx(1.0 * 0.0124 * (0.692 ** 2) * (0.98823 ** 3))
+    assert dc_flatten.bf == approx(1.0 * 0.0124 * (0.692**2) * (0.98823**3))
 
 
 def test_DecayChain_flatten_with_stable_particles():
@@ -317,7 +317,7 @@ def test_DecayChain_flatten_with_stable_particles():
     assert dc_flatten.decays[dc_flatten.mother].daughters == DaughtersDict(
         {"pi0": 4, "pi+": 3, "pi-": 2}
     )
-    assert dc_flatten.bf == approx(0.5 * (0.0124 ** 2) * (0.692 ** 2))
+    assert dc_flatten.bf == approx(0.5 * (0.0124**2) * (0.692**2))
 
 
 def test_DecayChain_string_repr(dc):