Check into HPDirect see if they do it, where you are. Basically I pay £3 per month ( not noticeable ) and I get to print 100sheets, doesn't matter if there is 1 letter or it's full A4 photo hires fancy paper. When the cartridges which are big get to 1/2 full your printer orders the required ink without you realising it and your like, ohhh what's this package, so you never run out or have to worry about damn ink and it's CHEAP as chips. Charge if you go over 6p per page, or you can sign up for more pages if required.
Canon appears to do the same thing. Sounds like a nice feature. I'm definitely looking into it. Math_Wiz
The trick to print charts is to print on white background. Keeps the charts clean and easily legible and does not use much ink/toner.
I was about to write this as well. Saves ink and you don't drench the paper. The price bars also tend to become sharper and better visible when no background color is printed. A white background also enables annotations in the chart area.