diff --git a/log-analytics/calculate-the-average-size-of-perf-usage-reports-per-computer.md b/log-analytics/calculate-the-average-size-of-perf-usage-reports-per-computer.md
index 7c358b6..d271862 100644
--- a/log-analytics/calculate-the-average-size-of-perf-usage-reports-per-computer.md
+++ b/log-analytics/calculate-the-average-size-of-perf-usage-reports-per-computer.md
@@ -1,15 +1,12 @@
-## Calculate the average size of perf usage reports per computer
+## Calculate the average data volume size of perf usage reports per computer
 #### #avg #sort #barchart
 <!-- article_id: 3107‎2017‏‎03827034 -->
 
 This example calculates the average size of perf usage reports per computer, over the last 3 hours.
 The results are shown in a bar chart.
 ```OQL
-Usage 
+Perf
 | where TimeGenerated > ago(3h)
-| where DataType == "Perf" 
-| where QuantityUnit == "MBytes" 
-| summarize avg(Quantity) by Computer
-| sort by avg_Quantity desc nulls last
-| render barchart
-```
\ No newline at end of file
+| where _IsBillable == true
+| summarize AvgBytes=avg(_BilledSize) by  Computer | sort by AvgBytes desc
+```