Non-Defense Discretionary Spending (NDD) is only a small portion of the total budget, and it has fallen over time. Between 1970 and 2013, NDD spending dropped from 9.6% to as low as 3.0% in 2013, a historic low.
Generally, it stays around 3-4% of GDP, hovering near 3.5% of GDP throughout 2013. There have been several notable exceptions. The first was between 1975 and 1981, when it was around 5 percent on average, and the second was between 2009 and 2011, when the American Recovery and Reinvestment Act and other governmental responses to the economic recession pushed NDD spending up to around 4 percent.
NDD spending can often be varied, complex, and controversial, ranging from diplomacy and international affairs to education, and various other items.
As the chart above from the Center on Budget and Policy Priorities shows, NDD spending generally falls into several categories:
Healthcare and Health Research (not including Medicare and Medicaid) make up about 20% of total NDD spending — that’s about $122 billion per year. Nearly half include hospital services to veterans, medical research done via the National Institutes of Health (25%), and other health programs such as the FDA, Center for Disease Control and Prevention and Indian Health Service.
Transportation and Economic Development cost $107 billion in 2015, or about 18% of all NDD spending. Transportation programs including the National Highway System and airport security make up the bulk of this area, with the rest going to various community programs such as disaster insurance and loans to farmers.
Science, Environment and Energy programs were 12% ($70 billion) of NDD spending in 2015, according to CBPP. The National Park System, NASA, and the Environmental Protection Agency (EPA) are included here.
Diplomacy and International Affairs make up $52 billion, or 9%, of NDD spending. About half of the spending was on humanitarian ventures such as international disaster relief and aid, funding for HIV/AIDS research, the Peace Corp, and contributions to international humanitarian agencies; about 21% goes toward security programs such as peacekeeping and nonproliferation efforts. 28% went to US embassies and consulates.
Law Enforcement and Governance is about 11%, or $65 billion, of NDD spending. Most of these funds — about three-fourths — go to law enforcement, the Department of Justice, correctional programs, border patrol, and anti-drug trafficking efforts; the rest funds the Internal Revenue Service, Congress, The Supreme Court, and the Government Accountability Office.
Education and Training count for 15% — around $90 billion of NDD spending in 2015. Most of the money goes to the Department of Education through K-12 programs, Pell Grants, and low-income assistance programs like Head Start, while the rest goes for job-training programs through the Workplace Investment Act as well as job placement and educational programs for Veterans.
Finally, Economic Security programs take up about $79 billion, or 14%. This money goes to social welfare programs such as WIC, food supplemental programs to needy families, homelessness prevention, housing assistance, and other housing subsidies. Funds also go to energy subsidies for low-income families, housing assistance for Veterans, and costs associated with Social Security Administration.