 The safety benefit is the gain in health-adjusted life expectancy HALE, or life extension expected upon implementation of the program.The cost effects must also be evaluated, measured as the effect on the real gross domestic product per person (with refinements that could include correction for purchasing power parity for international comparisons).The net benefit of a program is measured, according to the SCCR, by the resultant increases in real gross domestic product per capita and life expectancy, weighted by K. The Life Quality Index may be thought of as a refinement of monetary measures commonly used in cost-benefit analysis.