care than people in other countries. the u.s. consumes 3 times as many mammograms, 2.5x the number of mri scans, and 31% more c-sections per-capita than peer countries. this is a blend of higher per-capita income and higher use of specialists, among other factors. the u.s. government intervenes less actively to force down prices in the united states than in other countries. in the u.s., government accounts for 48% of healthcare spending, versus 76% in europe; this ratio of spending can be viewed as a proxy for bargaining power. stanford economist victor fuchs wrote in 2014: "if we turn the question around and ask why healthcare costs so much less in other high-income countries, the answer nearly always points to a larger, stronger role for government. governments usually eliminate much of the high administrative costs of insurance, obtain lower prices for inputs, and influence the mix of healthcare outputs by arranging for large supplies of primary-care physicians and hospital beds while keeping tight control on the number of specialist physicians and expensive technology. in the united states, the political system creates many "choke points" for diverse interest groups to block or modify government's role in these areas." in december 2011, the outgoing administrator of the centers for medicare & medicaid services, dr. donald berwick, asserted that 20% to 30% of health care spending is waste. he listed five causes for the waste: (1) overtreatment of patients, (2) the failure to coordinate care, (3) the administrative complexity of the health care system, (4) burdensome rules and (5) fraud. the institute of medicine reported in september 2012 that approximately $750b per year in u.s. health care costs are avoidable or wasted. this included: unnecessary services ($210 billion annually); inefficient delivery of care ($130 billion); excess administrative costs ($190 billion); inflated prices ($105 billion); prevention failures ($55 billion), and fraud ($75 billion). relative to prior years the congressional budget office analyzed the reasons for healthcare cost inflation over time, reporting in 2008 that: "although many factors contributed to the growth, most analysts have concluded that the bulk of the long-term rise resulted from the health care system's use of new medical services that were made possible by technological advances..." in summarizing several studies, cbo reported the following drove the indicated share of the increase (shown as a range across three studies) from 1940 to 1990: technology changes: 38-65%. cbo defined this as "any changes in clinical practice that enhance the ability of providers to diagnose, treat, or prevent health problems." personal income growth: 5-23%. persons with more income tend to spend a greater share of it on healthcare. administrative costs: 3-13%. aging of the population: 2%. as the country ages, more persons require more expensive treatments, as the aged tend to be sicker. several studies have attempted to explain the reduction in the rate of annual increase following the great recession of 2007-2009. reasons include, among others: higher unemployment due to the recession, which has limited the ability of consumers to purchase healthcare; rising out-of-pocket payments; deductibles (the amount a person pays before insurance begins to cover claims) have risen sharply. workers must pay a larger share of their own health costs, and generally forces them to spend less; and the proportion of workers with employer-sponsored health insurance enrolled in a plan that required a deductible climbed to about three-quarters in 2012 from about half in 2006. in september 2008 the wall street journal reported that consumers were reducing their health care spending in response to the current economic slow-down. both the number of prescriptions filled and the number of office visits dropped between 2007 and 2008. in one survey, 22% of consumers reported going to the doctor less often, and 11% reported buying fewer prescription drugs. cost forecasts spending for government healthcare programs is projected to rise significantly relative to gdp in the upcoming decades. the health and human services department expects that the health share of gdp will continue its historical upward trend, reaching 19.6% of gdp by 2024. the non-partisan congressional budget office (cbo) reported in march 2017 that healthcare cost inflation and an aging population are primary drivers of increasing budget deficits over time, as outlays (spending) continue to rise faster than revenues relative to gdp. cbo forecast that spending on major healthcare programs (including medicare and medicaid) would rise from 5.5% gdp in 2017 to 9.2% gdp by 2047. the medicare trustees provide an annual report of the program's finances. the forecasts from 2009 and 2015 differ materially, mainly due to changes in the projected rate of healthcare cost increases, which have moderated considerably. rather than rising to nearly 12% gdp over the forecast period (through 2080) as forecast in 2009, the 2015 forecast has medicare costs rising to 6% gdp, comparable to the social security program. the increase in healthcare costs is one of the primary drivers of long-term budget deficits. the long-term budget situation has considerably improved in the 2015 forecast versus the 2009 forecast per the trustees report. payment systems