[embed]https://www.youtube.com/watch?v=65E2kT4YTPQ&index=3&list=PLV0a-KDlEkvs_BCezu3MkNxIfTd5nMFVF[/embed]

The same way your car's gas mileage fluctuates when you go up a hill or pull a trailer, so too does your actual toner yield when you put more toner on a page. Every time you add a logo, chart or some other graphic, the more you pay per page.