Get Salary Level

CREATE FUNCTION ufn_GetSalaryLevel(@salary DECIMAL(18,4))
RETURNS NVARCHAR(20)
                AS
             BEGIN
           DECLARE @salaryLevel NVARCHAR(20)
            SELECT @salaryLevel =
              CASE
              WHEN @salary < 30000 THEN 'Low'
	         WHEN @salary BETWEEN 30000 AND 50000 THEN 'Average'
	         WHEN @salary > 50000 THEN 'High'
               END
RETURN @salaryLevel
END