Equities “are now barely through an 18-year secular bear market,” says our favorite underground analyst David Rosenberg. As illustrated by the nearby chart, US stocks have a historical tendency to move in 18-year cycles.

This is the fifth installment of a new Money Morning series highlighting investment opportunities in the global bull market in commodities. Soaring prices of grains, dairy and meat have been grabbing global headlines. But other commodities have been on the rise as well.