echorley,
Try using formula below
=Switch([Field1] Between 1 And 0.9,"A",[Field1] Between 0.89 And 0.8,"B",[Field1] Between 0.79 And 0.7,"C",[Field1] Between 0.69 and 0.00,"F")
Ken,
Don't you think switch function would be more appropriate to use for grading system.
hth,
Michael