One employee of the company has been working since April 2004. The company was not covered under the gratuity act since 2011-12 as it had fewer than 10 employees. However, in the year 2011-12, the company became covered by the gratuity act. The employee resigned in the year 2015-16. How should the gratuity of the employee be calculated? Let's assume his basic salary was 25,000 at the time of resignation.