See the attached image for further reference. The image is shown with an example, of defining slab for professional tax.
i.e., If the BP is less than 5000 then PT is 60,
if BP is between 5000 and 10000, PT = 100,
if BP is between 10000 and 15000, PT = 150 and
if BP is greater than or equal to 15000, PT = 200.
The image is shown with above example.