Can incentive income club into net profit

Respected sir, I have proprietorship firm doing business of cloth trading ,in that net profit is coming less than 8% , one thing i want to ask you that Is incentive received on turnover can be assume as business income and can add into net profit for fulfill the requirement of net profit must be 8% on turnover please guide. my tax consultant is saying that it can not be club into net profit, it will be income from other sources ,please guide. Incentive income we received as sales promotion and on turnover schemes