About Comparative using set analysis

[#1]

Hello! How can I do that using set analysis with that dimension, because with I take out dimension It´s working.

I used that expression below:

((Sum ({< Month_Num = {"<=$(vr_mes)"}, Month = >} Valor))

+

(Sum ({<Year = {$(vr_ano_anterior)}, Month = {'Dec'}>} Valor))

I need the dimension (month\year) has included on the chart.

Someone can help me?

Thank's

[#2]

Give a look in attached example. Need to be improved, but I believe will to help.