as policy numbers rise, the likelihood of claims rise. as the likelihood of claims rise, premiums increase because of the likelihood of loss. insurance companies don't like losses, they are not in business to pay losses, they are in business to invest premiums in profitable investments. paying losses decreases their potential to make a profit. increasing premiums hedges that that loss potential. anybody who really knows anything the about the insurance industry, knows that they are not in business to pay claims who's likelihood increases with increasing policy numbers. ask anyone who lives in a state that has mandatory auto insurance laws if their premiums actually went down after the law was enacted.