Thanks Martin.

So I started tested with you code before I realised the .currentmember property only works at Hierarchy level.

I modified my code to now look like the below.

CASE WHEN [Measures].[End LIS] = 0

AND SetToStr([Dim Date].[FSCL_YM].currentmember) = "[Dim Date].[FSCL_YM].[Month Nm].&[" + Format(now(), "yyyy") + "]&[" + Format(now(), "m") + "]"

THEN

CASE WHEN [Measures].[BEGIN_LIS] = 0 OR [Measures].[BEGIN_LIS] + [Measures].[BEGIN_LIS] + [Measures].[NETACTIVATIONS] = 0 THEN NULL ELSE

ROUND([Measures].[Disconnects]/(([Measures].[BEGIN_LIS] + [Measures].[BEGIN_LIS] + [Measures].[NETACTIVATIONS])/2) * 100 ,2) END

ELSE

CASE WHEN [Measures].[BEGIN_LIS] = 0 THEN NULL ELSE ROUND(([Measures].[Disconnects] / [AVERAGELIS] * 100) ,2)END

END

The code appears to work but is "jumping" over the case statement to moving to the ELSE portion as it is not evaluating the dim date value.

I have attached a screenshot of what my date hierarchy looks like for [FSCL_YM]. An example value from the hierarchy for 2015 July is

[Dim Date].[FSCL_YM].[Month Nm].&[2011]&[7]