diff --git a/rotation/simple_rotation.py b/rotation/simple_rotation.py
index 3f007f5..0caf119 100644
--- a/rotation/simple_rotation.py
+++ b/rotation/simple_rotation.py
@@ -109,7 +109,7 @@ def vol_adjusted_momentum_score(prices: np.ndarray) -> float:
 
 
 def slope_r2_score(prices: np.ndarray) -> float:
-    """Slope * R^2 score (unweighted, normalized prices)"""
+    """Slope * R² score (unweighted, normalized prices)"""
     if len(prices) < 5:
         return 0.0
     prices = np.clip(prices, 0.01, None)