Multi color 1 bar chart

Hello there,

I never used charts before and I have to admit that I am a little lost

what I need is a single bar chart for every month in a year, so 12 bars...

I need grades on my bar... lets say that the bar is set at 200...
from 0-100, bar must be a certain color (objective not met)
from 100-150, that portion of bar another color (within objectives)
over 150, that portion of bar another color (exceeded objectives)

any help would be appreciated

thanks,
Climbo