The issue arises only when the employer adds performance allowance, commision, incentives etc as part of gross salary for deciding whether he is paying the statutory minimum wages. For the purpose of PF contribution these components of salary could be excluded. After all when the employer can restrict payment of PF on a salary of Rs 15000, what is the relevance of gross salary being inflated with commision, incentives etc? But in respect of employees covered by ESI, these elements will be treated as part of wages provided these components are paid every month.