How to find whether employees are happy or not?

1. By using attendance we can track, because happy employees they don’t take more leaves.
2. Persons who won’t show any initiatives towards company events.
3. Don’t share any ideas to improve the product or services while discussing that in team meetings.
4. Always need to track the production and quality rate, which will helps to identify the unhappy employees. “Happy Employees Production and Quality will be high.”
5. Conduct surveys and also get open feedback from employees.
6. Just analyzing their current attitudes with past attitudes [Joining time].