Hiding column in same group based on month parameter

Hi,

I need to a make MTR column visible of the same group, based on user selection(i.e. need to create prompt),also it should be dependent on the month parameter which is already created.So if the month is Between Sept to Apr,then MTR parameter(prompt) should be active else if the other months are selected MTR column should be grayed.

Below is the representation of the matrix

Regards

Archana