There is a fundamental marketing concept called “Share of Voice,” which can be defined as follows: the ratio of the portion of advertising activities for one company or brand compared with the total advertising activities for an entire sector or product type. Take, for example, the auto insurance industry. If you watch TV, you’re almost certainly familiar with ads from Geiko, Progressive, Nationwide, State Farm, Esurance, and Farmers. Each of these companies possesses a “Share of Voice” that is roughly equivalent to the ratio between their respective advertising budget and the total advertising budget for the car insurance industry. Depending on the effectiveness of their advertising, each drives a portion of the overall demand for automotive insurance products. But since they’re all basically selling the same product, the real impact of their advertising doesn’t go much farther than encouraging consumers to purchase their respective generic offering instead of one of their competitor’s. And their advertising efforts are all aimed towards slicing up a pie that is fixed in overall size, because everyone who has a car is compelled by state regulations to purchase auto insurance.