27 % of workers are not achieving 240 working days - not interested to give annual increment

We are not interested in giving the annual increment to our workers because 27% of the workers are not achieving 240 working days. Basically, they are a leader-type workers, and their performance and behaviors are also very poor on the shop floor. All the workers are contract workers. Please provide some legal solutions to help solve my issues.

If all the workers are contract workers, why do you bother for annual increments? If the contract is an every-year-renewable contract agreement, the contractor himself will approach you for an enhancement in their service contract charges.

Thanks,
R. K. Nair