inventory replenishment forcasting, new workbook

I am looking to create a new workbook to assist me in forcasting parts replenishment dates and volumes for our 50 workstations. Currently the stations call in prior to running out of any of the 5 different parts but not always. Because the assembly times very so much the replenishment days are not always the same. I need a sheet that will help me say " if station 1 had parts delivery on the 5th, 7th, 9th, and 12th, of nearly the same volume of parts each time. Its next most likely date to need a shipment of parts is: and the volume is:

Anyone want to help me get started??

I always get such great help on this forum until I try this question. I've worded it several ways and never get much, if any, response. I have put together some data but didn't want to attach it because I am afraid whoever looks at it may want to leave the format the same and I am looking for layout assistance on this one. I'll throw it up her one more time. Anything anyone has to offer would be appreciated.

No replies either mean no one knows or its slipped under the radar.

What you are asking here is for excel to forecast the next day they will want to order and the order quantity. No easy task as it will involve complex matrices.

It wont be a an expontential curve (y=b*m^x) becasue as date increases the quantity won't

The quantity and date orders currently arent linear as a linear trend would be y=mx+b

But between the two would be closer to linear, though this would be awefully inaccurate, and becasue of this it will be hard to 'predict'.

I'd suggest googling something along the lines of 'sales forcasting' or 'excel trend forcasting'.

In your case you're wanting to forcast both varibles, date and quantity.

OK. thats a great start. I agree its a huge "idea". How about if we take the dates out of the equasion and make it predict daily and when I see the right quantities I can flag the date. Or set some validations that will flag the row when predetermined quantities are met and copy it to another sheet.

Also would need to it to be able to evolve. If it predicts a specific quantity for a day but production increases for some reason and at the last minute I deliver a greater quantity, that the daily use forcast also begins to adjust. Or was that a given?

The work stations parts requirements and replenishment dates seem so routine. Has anyone ever run across a sheet that helps predict supply of anything.