diff --git a/specification/monitor/resource-manager/microsoft.insights/stable/2015-04-01/autoscale_API.json b/specification/monitor/resource-manager/microsoft.insights/stable/2015-04-01/autoscale_API.json
index e54fae6a7958..e154f6651b8e 100644
--- a/specification/monitor/resource-manager/microsoft.insights/stable/2015-04-01/autoscale_API.json
+++ b/specification/monitor/resource-manager/microsoft.insights/stable/2015-04-01/autoscale_API.json
@@ -393,7 +393,8 @@
             "Minimum",
             "Maximum",
             "Total",
-            "Count"
+            "Count",
+            "Last"
           ],
           "x-ms-enum": {
             "name": "TimeAggregationType",