At the Daily Journal Corporation Annual Shareholders’ Meeting 2018 (14-Feb-2018,) Charlie Munger was asked, “In 1999, Warren Buffett said that he could return 50% if he ran $1 million. Give what you said about the investment landscape today being more difficult, what do you think that number would be today?” His response:

Well I do think that a very smart man who’s patient and aggressive in combination, is willing to work hard, to root around in untraveled places like thinly traded stocks and other odd places. I do think a person with a lot of shrewdness, working with a small amount of capital, can probably earn high returns on capital even today.

…

Generally speaking, I would say, if you’re shrewd enough with small sums of money, I think you can compound pretty well. The minute you get bigger sums, I think it starts getting difficult. It’s way more difficult for all you people sitting here than it was for me when I was in your position. But I’m about to die and you have a lot of years ahead.

Source: Charlie Munger aficionado Richard Lewis’s thorough transcript at his Lattice Work Investing blog.