I must admit I'm not sure what you're asking. This is what I think you're

eluding to:

- You want a parts table, and a systems table.

- Another table to tracks part failures with Month and PartID and another to

track system failures with Month and SystemID

- and lastly for a given month, divide the count of parts failed in a month

with the count of systems failed in that month.

Does that look like where you're heading?

Dominic

<lu**************@philips.comwrote in message

news:fb**********************************@v29g2000 hsf.googlegroups.com...

Hello!

I'm a new Access user and I believe I'm facing a problem that can be

solved easily, but I don't know how.

My goal is to calculate monthly failure rates A failure rate is the

result of dividing used parts by the number of systems. For example.

There is a set of used parts {a,b,c,d,e} and a set of systems

{g,h,i,j,k}. These sets are monthly updated. Now I would like to get

time-series for different failure rates calculated by for example

{a,b}/{g,h,i} and {c,d,e}/{h,j,k}. The number of used parts varies

every month and the number of systems will increase every month, this

has to be taken into calculation.

Can somebody please help me. If my problem is not clear enough, I can

explain it in more detail.

Thanks in advance!