diff --git a/models.go b/models.go
index 3d729fd..cef025d 100644
--- a/models.go
+++ b/models.go
@@ -12,7 +12,7 @@ type Filter struct {
 	Name     string    `form:"filter_name" yaml:"filter_name" json:"filter_name" binding:"required" validate:"min=1"`
 	X        int       `form:"x" yaml:"x" json:"x" validate:"default=0"`
 	Y        int       `form:"y" yaml:"y" json:"y" validate:"default=0"`
-	Type     string    `form:"filter_type" yaml:"filter_type" json:"filter_type" binding:"required" validate:"oneof=url xpath json css replace match substring min max average count"`
+	Type     string    `form:"filter_type" yaml:"filter_type" json:"filter_type" binding:"required" validate:"oneof=url xpath json css replace match substring math"`
 	Var1     string    `form:"var1" yaml:"var1" json:"var1" binding:"required"`
 	Var2     *string   `form:"var2" yaml:"var2" json:"var2"`
 	Var3     *string   `form:"var3" yaml:"var3" json:"var3"`
diff --git a/scraping.go b/scraping.go
index 60aa5e2..e33aff9 100644
--- a/scraping.go
+++ b/scraping.go
@@ -72,22 +72,28 @@ func getFilterResult(filter *Filter) {
 		{
 			getFilterResultSubstring(filter)
 		}
-	case filter.Type == "min":
+	case filter.Type == "math":
 		{
-			getFilterResultMin(filter)
-		}
-	case filter.Type == "max":
-		{
-			getFilterResultMax(filter)
-		}
-	case filter.Type == "average":
-		{
-			getFilterResultAverage(filter)
-		}
-	case filter.Type == "count":
-		{
-			getFilterResultCount(filter)
+			switch {
+			case filter.Var1 == "min":
+				{
+					getFilterResultMin(filter)
+				}
+			case filter.Var1 == "max":
+				{
+					getFilterResultMax(filter)
+				}
+			case filter.Var1 == "average":
+				{
+					getFilterResultAverage(filter)
+				}
+			case filter.Var1 == "count":
+				{
+					getFilterResultCount(filter)
+				}
+			}
 		}
+
 	default:
 		log.Println("getFilterResult called with filter.Type == ", filter.Type)
 	}
diff --git a/static/edit.js b/static/edit.js
index f95b430..a1831cd 100644
--- a/static/edit.js
+++ b/static/edit.js
@@ -279,6 +279,7 @@ function onTypeChange(node) {
         }
         case "math": {
             var mathSelect = document.createElement("select");
+            mathSelect.name = "var1";
             mathSelect.id = "var1Input";
             mathSelect.classList.add("form-control");
             var mathOptionMin = document.createElement("option");
diff --git a/static/edit.ts b/static/edit.ts
index 81e1de9..2bd12db 100644
--- a/static/edit.ts
+++ b/static/edit.ts
@@ -268,6 +268,7 @@ function onTypeChange(node: DiagramNode | null = null){
         }
         case "math": {
             let mathSelect = document.createElement("select");
+            mathSelect.name = "var1";
             mathSelect.id = "var1Input";
             mathSelect.classList.add("form-control");
             let mathOptionMin = document.createElement("option");