Introduction
When investing in the stock market, we all can not see the future. Nevertheless, there are statistically more or less certainties that investors should take into account in their considerations. One of these completely banal certainties is that every upswing is followed by a downturn. Since the financial crisis of 2009, the stock markets, especially in the USA, have known only one way. In such phases investors can quickly get used to the condition of rising prices. Therefore, investors always have to take into account that a recession will certainly occur at some point.