A company has only three members: a manager, a secretary, and a salesperson. If only the secretary receives a 10\% salary increase, the company's total salary expenditure increases by 3\%; if only the salesperson receives a 20\% salary increase, the company's total salary expenditure increases by 4\%. If only the manager's salary is reduced by 15\%, then the company's total salary expenditure will decrease by (12).(13)\%.