From the Summary: "Federal agencies issue thousands of regulations each year under delegated authority from Congress. Over the past 70 years, Congress and various Presidents have created a set of procedures agencies must follow to issue these regulations, some of which contain requirements for the calculation and consideration of costs, benefits, and other economic effects of regulations. In recent years, many Members of Congress have expressed an interest in various regulatory reform efforts that would change the current set of rulemaking requirements, including requirements to estimate costs and benefits of regulations. As part of this debate, it has become common for supporters of regulatory reform to comment on the total cost of federal regulation. Estimating the total cost of regulations is inherently difficult. Current estimates of the cost of regulation should be viewed with a great deal of caution."
CRS Report for Congress, R44348
Federation of American Scientists: http://www.fas.org/sgp/crs/index.html