diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index ffac0046e0f..06317f6f8f6 100644
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -760,7 +760,7 @@ namespace {
                     + 18 * pawnsOnBothFlanks
                     + 49 * !pos.non_pawn_material()
                     -  2 * pos.rule50_count()
-                    - 11 * pos.aging()
+                    -  9 * pos.aging()
                     -121 ;
 
     // Now apply the bonus: note that we find the attacking side by extracting