diff --git a/radiation/p1adjoint/of_grad_cd.csv.ref b/radiation/p1adjoint/of_grad_cd.csv.ref
index 84d9e955..ac404c8e 100644
--- a/radiation/p1adjoint/of_grad_cd.csv.ref
+++ b/radiation/p1adjoint/of_grad_cd.csv.ref
@@ -1,6 +1,6 @@
 "VARIABLE"      , "GRADIENT"      , "FINDIFF_STEP"  
 0               , -0.000954218    , 0.001           
-1               , -0.00432385     , 0.001           
+1               , -0.00432384     , 0.001
 2               , -0.0111485      , 0.001           
 3               , -0.0214656      , 0.001           
 4               , -0.0344212      , 0.001