Just like they have ways to calculate poverty rate - anyone living below a certain amount -, they have ways to calculate this as well. Also the article said that only 500 million Indians are part of the workforce.
Actually I forgot something interesting. The labourer makes 100 rupees per day. That labourer probably is feeding a wife and children, maybe parents as well.
Nope in here ,usually all family members go to work unless he/she is sick or is not interested..Usually like house maid jobs and cleaning jobs or even panchayat jobs/muncipality/corporation jobs.
