Professional tax - on which amount of salary we deduct Professional Tax?

I have to deduct professional tax, so can you please tell me on which amount of salary we deduct Professional Tax?
suppose monthly gross for 30 days is 3000 Rs but employee work for 25 days and the gross salary is 2500 then on which amount we have to deduct Professional Tax? On Rs 3000 or Rs 2500?

PT need to be deducted on actual earnings only....i.e. 2500.00