Dear venkat sir
This was the mode were seats will be occupied in different trains based on travel time.
1. Day time trains like jan sathabdi express, intercity express trains like pallavan and brindavan express will have more demand for chair car and less for second sitting due to heat outside.
2. Night time trains like cheran and pandiyan express trains will have more...
more... demand for sleeper class then ac3 tier then ac2 tier then ac1st class and last option is for non ac 1st class.
3. In long distance trains like tamil nadu and coromandel express trains have preference to available class of maximum vacancy
The worst jail of indian railways was the unmaintained non ac 1st class this is due to doors available for locking the cabin which creates huge amount sweat.