Another Invalid Coercion from a newbie

[kimmal]

Source: a TM1 cube
Problem: trying to dynamically display 3 years of data based on the current fiscal year

Description: I have a time dimension (Fiscal_Period) that has the following rollup member: Fiscal Periods, YTD, Forecastable Periods.  Within those members are the years, so Fiscal Periods has 2015, 2016, 2017, 2018.  The dimension (Fiscal_Period) also has attributes attached to each period one of them being "is_current_year".  Our fiscal year end is February.  So in Jan/16 and Feb/16 the current fiscal year is 2016 and in March/16 onward its 2017.

We want the report to show CY, CY+1 and CY+2 data in the columns but don't want to have to go in and change the report every year, so we added the "is_current_year" attribute.

I can get the CY to pick up the right year using the following statement: filter (children([Fiscal Periods]),[TM1 ExpCt].[Fiscal_Period].[Fiscal_Period].[is_current_year]='Y' and [TM1 ExpCt].[Fiscal_Period].[Fiscal_Period].[level_num] = 2), but from there I can't figure out how to get CY+1 and CY+2.  Tried nextMember but it doesn't work, that's where I get the coercion error.

Thoughts?