Connection Formula - Current and Previous Member

Question

I am using SharePoint 2013 and PerformancePoint Dashboard Designer 2013. I have a Filter and a Chart in a Dashboard Page. When I select a member in a Filter, I want the Chart to display data for Current Member and one Previous Member.

In the Connection Formula Dialogue, I used following two formulas but it only displays data for Current Member only in both cases.

LastPeriods
(2,
 {<<SourceValue>>}.item(0)
)

And

LastPeriods
(2,
 {<<UniqueName>>}.item(0)
)

Please correct me.

Answer 1

LastPeriods
{2,
<<UniqueItem>>
} 

worked for me.