Gratuity Calculation Confusion: Why Is It 4.81% in CTC Instead of Years Worked?

Gratuity Calculation

Hi, I am a student in need of some clarification about gratuity calculation.

How is gratuity calculated at 4.81% in every CTC breakup, whereas until now, I have studied that it is calculated based on the number of years an employee has worked?

Employee works for 26 days on average per month, totaling 26 * 12 = 312 days per year. According to the Act, 15 days' salary is to be paid for one completed year. Therefore, the percentage comes to 15 * 100 / 312 = 4.80769230769231, which is rounded off to 4.81%. I hope this calculation is clear.

Why Do Companies Include Gratuity in CTC?

Why do companies include the gratuity amount as part of the CTC? Why is 4.81% of the monthly basic salary deducted or retrieved from the monthly salary?

What Should Employees Do?

What should an employee do if the company is deducting 4.81% of the monthly basic salary when they are not supposed to do so?

Thank you.