Index: source/simulation2/system/ComponentManager.cpp
===================================================================
--- source/simulation2/system/ComponentManager.cpp
+++ source/simulation2/system/ComponentManager.cpp
@@ -1104,28 +1104,16 @@
 
 std::string CComponentManager::GenerateSchema() const
 {
-	std::string numericOperation =
-		"<optional>"
-			"<attribute name='op'>"
-				"<choice>"
-					"<value>add</value>"
-					"<value>mul</value>"
-				"</choice>"
-			"</attribute>"
-		"</optional>";
 	std::string schema =
 		"<grammar xmlns='http://relaxng.org/ns/structure/1.0' xmlns:a='http://ns.wildfiregames.com/entity' datatypeLibrary='http://www.w3.org/2001/XMLSchema-datatypes'>"
 			"<define name='decimal'>"
 				"<data type='decimal'/>"
-				+ numericOperation +
 			"</define>"
 			"<define name='nonNegativeDecimal'>"
 				"<data type='decimal'><param name='minInclusive'>0</param></data>"
-				+ numericOperation +
 			"</define>"
 			"<define name='positiveDecimal'>"
 				"<data type='decimal'><param name='minExclusive'>0</param></data>"
-				+ numericOperation +
 			"</define>"
 			"<define name='anything'>"
 				"<zeroOrMore>"
Index: source/simulation2/system/ParamNode.cpp
===================================================================
--- source/simulation2/system/ParamNode.cpp
+++ source/simulation2/system/ParamNode.cpp
@@ -83,7 +83,8 @@
 	enum op {
 		INVALID,
 		ADD,
-		MUL
+		MUL,
+		MUL_ROUND
 	} op = INVALID;
 	bool replacing = false;
 	bool filtering = false;
@@ -117,6 +118,8 @@
 					op = ADD;
 				else if (std::wstring(attr.Value.begin(), attr.Value.end()) == L"mul")
 					op = MUL;
+				else if (std::wstring(attr.Value.begin(), attr.Value.end()) == L"mul_round")
+					op = MUL_ROUND;
 				else
 					LOGWARNING("Invalid op '%ls'", attr.Value);
 			}
@@ -178,7 +181,10 @@
 			node.m_Value = (oldval + mod).ToString().FromUTF8();
 			break;
 		case MUL:
-			node.m_Value = (oldval.Multiply(mod)).ToString().FromUTF8();
+			node.m_Value = oldval.Multiply(mod).ToString().FromUTF8();
+			break;
+		case MUL_ROUND:
+			node.m_Value = fixed::FromInt(oldval.Multiply(mod).ToInt_RoundToNearest()).ToString().FromUTF8();
 			break;
 		}
 		hasSetValue = true;