Excerpt: Aetna gives brokers a 'retention bonus' for staying loyal. If a broker keeps 90% of his Aetna clients with the insurer for another year, he gets a bonus equal to 0.75% of the clients' total premiums. If 100% stay, the bonus rises to 1.25% of total premiums. Though employers typically put their health-insurance contracts up for bid every few years, such bonuses are one factor encouraging brokers to keep their clients on the same plan.  MORE >>