There is an old investment scam where you start with sending a few thousand letters with half saying gold is going up and the other half saying gold is downing

There is an old investment scam where you start with sending a few thousand letters with half saying gold is going up and the other half saying gold is downing down. Initially, half the people got "good" investment advice. Send another letter to the people who got the "good" advice say the US dollar is going up or down spilt equally. Again, half the people got "good" advice, so send another letter to the people who got two lots of good advice ie a quarter of the original number. Continue to send letters to the "winners" with half saying buy a commodity and the other half to sell the same commodity. If you started with 2,000 marks after four letters you have 250 people who would have made "a very large ROI" if you had followed our investment advice. Then you sell them some very bad shit or a subscription to your investment newsletter. Morral: Past performance does not mean it will continue.