>
>For example, I could offer an increased discount for every 5 more licences like this:
>
>

# lic.	Price	Discount	 Cost 
>5	2400	0	 $2,400.00 
>10	2280	0.050	 $4,680.00 
>15	2220	0.075	 $6,900.00 
>20	2160	0.100	 $9,060.00 
>25	2100	0.125	 $11,160.00 
>30	2040	0.150	 $13,200.00 
>35	1980	0.175	 $15,180.00 
>40	1920	0.200	 $17,100.00 
>45	1860	0.225	 $18,960.00 
>50	1800	0.250	 $20,760.00 
>55	1740	0.275	 $22,500.00 
>60	1680	0.300	 $24,180.00 
>65	1620	0.325	 $25,800.00 
>70	1560	0.350	 $27,360.00 
>

>
>Which is a little complicated as I work out the discount for each tranch of 5 licences and then total everything.
>

That's way too many groupings. I'd do a break at maybe 15-20, another at 50, and one at 100+.