You can try this way.
Normally, performance pay is an annual payment, which will be in lieu of a bonus. This is more like sharing the profit of the business based on the business results and the employee's performance. To calculate the performance pay, the system that we follow is:
Individual performance is rated on a 5-band scale starting from Unsatisfactory to Exceptional, which is factored on a scale of 1 to 10. Company Performance is calculated on various factors, which will be assessed by the Top Management and is on a scale of 1 to 3.
For example: an individual is rated for his performance on the 5-band scale, and his corresponding incentive factor is 7.5. The company is rated 2.7 by the management. His incentive is calculated as follows:
7.5 x 2.7 = 20.25 x Gross Annual Cost / 100
For example, if his Gross Annual Cost is 400,000, his incentive would be 20.25% of his Gross Annual Cost, i.e., Rs. 81,000.
Hope this information is helpful to you.