diff --git a/src/js/slaveCostJS.js b/src/js/slaveCostJS.js
index d806f4083fb6f1a5768f838af26fae48867b1ac8..57e039ba0bd7807dd429bb617a5b98eab179c614 100644
--- a/src/js/slaveCostJS.js
+++ b/src/js/slaveCostJS.js
@@ -2084,7 +2084,7 @@ globalThis.FResultArray = (function() {
 		// missing limbs
 		adjustFResult(`Limbs: Missing`, -getLimbCount(slave, 0) * 0.5);
 		// non-sex prosthetics
-		adjustFResult(`Prosthetics: Non Sexual`, -getLimbCount(slave, 102) - getLimbCount(slave, 103) * 0.25);
+		adjustFResult(`Prosthetics: Non Sexual`, -(getLimbCount(slave, 102) - getLimbCount(slave, 103)) * 0.25);
 	}
 
 	/**