using variable in place of dimension in set analysis

[warrenpress]

Hi,

I currently have the following expression

sum({$<L4L_Flag_2014={'Y'}>} qty)

which i need to make dynamic using a variable called L4L_Flag

L4L_Flag is set using the follow expression

if(Year=2014,L4L_Flag_2014,L4L_Flag_2013)

How do i replace the L4L_Flag_2014 dimension in the initial expression with the variable L4L_Flag ??

I tried sum({$<$(L4L_Flag)={'Y'}>} qty) but to no avail.

Thanks in advance

[warrenpress]

Thanks tresesco.

I knew it had to be something simple.