Calculate shipping cost from quantity ordered

Hi, can anyone please please point me in the right direction here?
:wacko:

My site will be selling one kind of product to a local area.
So as far as shipping is concerened product weight and customer location is not a factor.

I need to be able to calculate the shipping cost based on quantity ordered, does anyone know if this is possible? and if so, how can this be set it up?

to be more specific my shipping costs are as follows....
Amount ordered \ shipping cost
up to 8 bags $3.50
9-16 bags $6.50
17-32 bags $8.50
33-48 bags $11.00
49-64 bags $13.50
65-76 bags $16.50
77-100 bags $18.50

Many thanks, Kev. :D

up to 8 bags $3.50
9-16 bags $6.50
17-32 bags $8.50
33-48 bags $11.00
49-64 bags $13.50
65-76 bags $16.50
77-100 bags $18.50

If there was a real pattern there something could be programmed, but ...

your first break point is- $3.50
2nd is - $6.50 ... 3.50+$3.00
next is - $8.50 ... 6.50+$2.00
and - $11.00 ... 8.50+$2.50
then - $13.50 ... 11.00+$2.50
and - $16.50 ... 13.50+$3.00
... $18.50 ... 16.50+$2.00