In 2019, U.S. residents aged 15 and older spent an average of 0.5 hours per day shopping, 4.1 hours on work & education, and 5.2 hours on leisure & sports. The material living standards of nations are primarily driven by how much people work and how productively they do it. These factors form the very definition of economic output, or gross domestic product, which is equal to "hours worked times labor productivity." America's total work hours and productivity tend to increase over time due to population growth and the advance of technology, but the rate of increase for both have been feeble compared to the past, and hence, so has economic growth. Many factors can affect work hours and productivity, but three of the most direct and drastically changing over recent years are government debt, regulations, and social programs. All of these have grown at rapid rates, which may explain why the U.S. (and many other nations) are experiencing weak economic growth.