Legal costs are now a major factor for U.S. firms to consider when marketing products and services. For example, they represent 95% of the price of childhood vaccines. Product liability is so important that many useful products, such as the IUD for birth control, have been removed from the market. Certain services, such as day care centers, are provided at high prices to cover liability exposure. Why have legal costs associated with products risen so rapidly since the early 1960s?