diff --git a/freqtrade/data/metrics.py b/freqtrade/data/metrics.py
index 77f29080c..de8ebac4a 100644
--- a/freqtrade/data/metrics.py
+++ b/freqtrade/data/metrics.py
@@ -261,8 +261,8 @@ def calculate_expectancy(trades: pd.DataFrame) -> tuple[float, float]:
     :return: expectancy, expectancy_ratio
     """
 
-    expectancy = 0
-    expectancy_ratio = 100
+    expectancy = 0.0
+    expectancy_ratio = 100.0
 
     if len(trades) > 0:
         winning_trades = trades.loc[trades["profit_abs"] > 0]
diff --git a/requirements-dev.txt b/requirements-dev.txt
index 91a233b3d..1907e9a0e 100644
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -8,7 +8,7 @@
 
 coveralls==4.0.1
 ruff==0.7.0
-mypy==1.11.2
+mypy==1.12.1
 pre-commit==4.0.1
 pytest==8.3.3
 pytest-asyncio==0.24.0