I want to build an expression for House Rent (HR) in MS Access.

If Basic Salary (BS) is =>5000, HR is 50% of BS but not less than 2250,

if BS is between 5001 and 10800, HR is 45% of BS but not less than 2500 and

if BS is between 10801 and 21600, HR is 40% of BS but not less than 4800