They say that difficulty in acquiring loan is the reason behind the plunge.
But car analysts says that above might not be the reason for plunge. They think its the series of fire catching incidents in the Nano, as well as price rises are the cause of concern for the affected sales.
It had sold just 509 Nanos during November 2010.
Tata offered free safety upgrades for the model, which went on sale last year.
This came after much media frenzy behind the fire catching incidents which were reported by six owners.