Industrialized economies progress through cycles of expansion, peaking, trough, and expansion again. It follows then that the major industries propelling those economies pass through four phases during their existence: introduction, growth, maturity, and decline. Those industries consist of separate companies, and of course, the securities issued by those companies tend to anticipate business cycles and move in the same direction.

When you look at a stock chart below, you can observe its price history and the cycles – or series of peaks and troughs – that it's completed so far.