Dynamic goal for a KPI?

Hi!

I'm new in SSAS and I'm stuck. Here's my problem :
The goal of my KPI has to change (every month or every year). I could enter these different values with an MDX expression such as

CASE WHEN <date condition>
THEN goal-1-value
...
END

but i'd like it (different values of the goal) to be stored in a database.
So my question is : Is it possible to get back these values from an MDX expression?
If not is there another way to get these values from database in SSAS?

Thanks in advance,

Philippe
Assuming that you do store the goal values in a table, you coud add a measure group, with a measure for the goal value, to the cube. Then this "goal" measure can be directly accessed in MDX.