diff --git a/src/index.js b/src/index.js
index a09a786..46b29b5 100644
--- a/src/index.js
+++ b/src/index.js
@@ -588,10 +588,10 @@ export default class Gantt {
         };
 
         const x_pos = {
-            'Quarter Day_lower': (this.options.column_width * 4) / 2,
-            'Quarter Day_upper': 0,
-            'Half Day_lower': (this.options.column_width * 2) / 2,
-            'Half Day_upper': 0,
+            'Quarter Day_lower': 0,
+            'Quarter Day_upper': this.options.column_width * 2,
+            'Half Day_lower': 0,
+            'Half Day_upper': this.options.column_width,
             Day_lower: this.options.column_width / 2,
             Day_upper: (this.options.column_width * 30) / 2,
             Week_lower: 0,