Statistics Collector Policy - Custom Dimension is not listing

[apiandintegr]

Hell All,

I have added a statistics collector policy to enable custom dimension. I

Below is the code,

<StatisticsCollector name="statisticscollector">
  <Statistics>
    <Statistic name="participant" ref="id" type="string">999999</Statistic>
  </Statistics>
</StatisticsCollector>

 I have added this in the proxy pre-flow, I can see in the trace that it has got executed. I was expecting participant as a dimension in dimension drop down, but for some reason it is not appearing in the drop down list. Am I missing anything ?