maintain the safey stock arround 10%

Hi there,

I have a requirement like this, suppose the client wants to buy 100 item M0001,

and the BOM for item M0001 is like this:

1. A0001 (1pcs)

2. B0001 (1pcs)

suppose i have on-hand inventory like below:

1. A0001(50 pcs on-hand)

2. B0001(10 pcs on-hand)

Suppose i have to maintain the satey stock arrount 10% of the sales/production order. when i finish running the master plan, i should get the purchase order like this:

1. A0001(60 pcs on-order)

2. B0001(100 pcs on-order)

how to handle this kind of requirements.

many thanks.