Economist Bibek Debroy,a member of NITI said that Rs. 2000 note is necessary & cost effective.He said that government will figure out ways to stop hoarding of black/undeclared money.It is a secret mission & cannot be revealed to many people.He also said that people will face difficulty for few days.He said most people standing in line are not there to swap their own old notes for new ones but are serving as proxies for others.