diff --git a/Calorimeter/CaloG4/EcalG4_SD/src/EcalSensorSD.h b/Calorimeter/CaloG4/EcalG4_SD/src/EcalSensorSD.h
index d558c0e74e1a55a1e0b3680d7f4831dc3ba66341..4f2c35638e42c29f2eafe2075bea2748ccf8d811 100644
--- a/Calorimeter/CaloG4/EcalG4_SD/src/EcalSensorSD.h
+++ b/Calorimeter/CaloG4/EcalG4_SD/src/EcalSensorSD.h
@@ -280,9 +280,9 @@ inline double EcalSensorSD::localNonUniformity (double x, double y) const
 
   // Local uniformity is product of x and y sine-like functions
   // The Amplitude of the sin-like function is a function of x and y
+  // Deion: changed LHCb's parametrization by adding the (- A_local) at the end in order to center the correction on zero
   if ( A_local > lowTolerance )
-    correction += A_local / 2. * ( 1. - cos( 2. * CLHEP::pi * (x-x0)/d ) ) *
-      ( 1. - cos( 2. * CLHEP::pi * (y-y0)/d ) ) ;
+    correction += A_local / 2. * ( 1. - cos( 2. * CLHEP::pi * (x-x0)/d ) ) * ( 1. - cos( 2. * CLHEP::pi * (y-y0)/d ) ) - A_local ;
 
   double rX(0.) , rY(0.) , hCell(0.) ;