diff --git a/class/core/system_api.py b/class/core/system_api.py
index dbe613a78..f576275e8 100755
--- a/class/core/system_api.py
+++ b/class/core/system_api.py
@@ -336,7 +336,7 @@ class system_api:
             tmp['path'] = disk[1]
             size_tmp = psutil.disk_usage(disk[1])
             tmp['size'] = [mw.toSize(size_tmp[0]), mw.toSize(
-                size_tmp[1]), mw.toSize(size_tmp[2]), str(size_tmp[2]) + '%']
+                size_tmp[1]), mw.toSize(size_tmp[2]), str(size_tmp[3]) + '%']
             diskInfo.append(tmp)
         return diskInfo