What is the right amount of tokens to keep for the company?

[inillo]

In most ICOs only part of the tokens are sold to the public. Typically, from 20% to 70%. If the company is too greedy, the smart money will run away (even tough nowadays there seems to be money for all kind of crap).

So, what would be in your view the right percent to put to the public so that the company has tokens to develop the project but the possible loss of value when they sell is not too much.