The farm bill is an omnibus, multi-year law that governs an array of agricultural and food programs. Although agricultural policies sometimes are created and changed by freestanding legislation or as part of other major laws, the farm bill provides a predictable opportunity for policymakers to comprehensively and periodically address agricultural and food issues. The farm bill is renewed about every five years. Since the 1930s, farm bills traditionally have focused on farm commodity program support for a handful of staple commodities such as corn, soybeans, wheat, cotton, rice, dairy, and sugar. Yet farm bills have grown in breadth in recent decades. Among the most prominent additions have been nutrition assistance, conservation, horticulture, and bioenergy programs. The omnibus nature of the farm bill can create broad coalitions of support among sometimes conflicting interests for policies that individually might not survive the legislative process. This can lead to competition for funds. In recent years, more parties have become involved in the debate, including national farm groups, commodity associations, state organizations, nutrition and public health officials, and advocacy groups representing conservation, recreation, rural development, faith-based interests, local food systems, and certified organic production. The Agricultural Act of 2014 ( P.L. 113-79 , H.Rept. 113-333 ), referred to here as the "2014 farm bill," is the most recent omnibus farm bill. It was enacted in February 2014 and expires mostly in 2018. It succeeded the Food, Conservation, and Energy Act of 2008 ( P.L. 110-246 , "2008 farm bill"). The 2014 farm bill contains 12 titles encompassing commodity price and income supports, farm credit, trade, agricultural conservation, research, rural development, energy, and foreign and domestic food programs, among other programs. (See titles described in the text box below.) Provisions in the 2014 farm bill reshaped the structure of farm commodity support, expanded crop insurance coverage, consolidated conservation programs, reauthorized and revised nutrition assistance, and extended authority to appropriate funds for many U.S. Department of Agriculture (USDA) discretionary programs through FY2018. Potential expiration and the consequences of expired law may also motivate legislative action. When a farm bill expires, not all programs are affected equally. Some programs cease to operate unless reauthorized, while others might continue to pay old obligations. The farm commodity programs not only expire but would revert to permanent law dating back to the 1940s. Nutrition assistance programs require periodic reauthorization, but appropriations can keep them operating. Many discretionary programs would lose statutory authority to receive appropriations, though annual appropriations could provide funding and implicit authorization. Other programs have permanent authority and do not need to be reauthorized (e.g., crop insurance). Figure 1 provides a timeline of selected important dates for U.S. farm bill policy and other related laws. In many respects, agricultural policy in the United States began with the creation of USDA, homesteading, and subsequent creation of the land grant universities in the 1800s. Many stand-alone agricultural laws were passed during the early 1900s to help farmers with credit availability and marketing practices, and to protect consumers via meat inspection. The economic depression and dust bowl in the 1930s prompted the first "farm bill" in 1933, with subsidies and production controls to raise farm incomes and encourage conservation. Commodity subsidies evolved through the 1960s, when Great Society reforms drew attention to food assistance. The 1973 farm bill was the first "omnibus" farm bill; it included not only farm supports but also food stamp reauthorization to provide nutrition assistance for needy individuals. Subsequent farm bills expanded in scope, adding titles for formerly stand-alone laws such as trade, credit, and crop insurance. New conservation laws were added in the 1985 farm bill, organic agriculture in the 1990 farm bill, research programs in the 1996 farm bill, bioenergy in the 2002 farm bill, and horticulture and local food systems in the 2008 farm bill. The farm bill authorizes programs in two spending categories: mandatory and discretionary. Mandatory spending programs generally operate as entitlements. A bill pays for them using multi-year budget estimates (baseline) when the law is enacted. Discretionary spending programs are authorized for their scope but are not funded in the farm bill. They are subject to annual appropriations. While both types of programs are important, mandatory programs often dominate the farm bill debate and are the focus of the farm bill's budget. When the current farm bill was enacted in February 2014, the Congressional Budget Office (CBO) estimated that the total cost of mandatory programs would be $489 billion for the 12-title farm bill over the five years FY2014-FY2018. Four titles accounted for 99% of anticipated farm bill mandatory outlays: nutrition, crop insurance, conservation, and farm commodity support. The nutrition title, which includes the Supplemental Nutrition Assistance Program (SNAP), comprised 80% of the total. The remaining 20% was mostly geared toward agricultural production across several other titles ( Table 1 ). Farm commodity support and crop insurance combined to be 13% of mandatory program costs, with another 6% of costs in USDA conservation programs. All other farm bill titles accounted for about 1% of all mandatory expenditures. Although their relative share is small, titles such as horticulture and research saw their shares increase compared to the 2008 farm bill. In the years since enactment of the farm bill, CBO has updated its projections of government spending several times a year based on new information about the economy and program participation. Outlays for FY2014-FY2016 have become final (actual), estimates are available for FY2017, and updated projections for FY2018 have generally reflected lower farm commodity prices and lower costs for SNAP. The new five-year estimated cost of the 2014 farm bill, as of April 2018, is $455 billion for the four largest titles, compared with $484 billion for those same four titles four years ago (right side of Table 1 ). This is $28 billion less than what was projected at enactment (-6%). Figure 2 shows these projections and actual outlays for the four major titles of the 2014 farm bill. The result of these new projections is that SNAP outlays are projected to be $26 billion less for the five-year period FY2014-FY2018 than was expected in February 2014 (-7%). Crop insurance is projected to be $10 billion less for the five-year period (-25%) and conservation programs about $5 billion less (-19%). In contrast, farm commodity and disaster program payments are projected to be about $13 billion higher than was expected at enactment (+55%) due to lower commodity market prices (which raises counter-cyclical payments) and higher livestock payments due to disasters. The cost of the farm bill has grown over time, though relative proportions across the major program groups have shifted ( Figure 3 ). Conservation program spending has steadily risen as conservation programs have become more numerous and expansive in their authorized scope. Farm commodity program spending has both risen and fallen with market price conditions and policy responses. For the past decade, though, program costs have generally decreased as counter-cyclical payments were smaller due to higher market prices. (This trend, however, has reversed at least temporarily as shown in the current projections for future farm bill spending [ Table 1 ]). Crop insurance costs have increased steadily as the program has expanded to cover more commodities and become a primary means for risk management. Higher farm commodity market prices and increased covered acreage have raised the insured value of production and consequently program costs. Crop insurance costs have overtaken the traditional farm commodity programs in total costs. Nutrition program assistance in the farm bill (SNAP) rose sharply after the recession in 2009 but has begun to decline more slowly during the recovery. The allocation of baseline among titles, and the size of each amount, is not a zero-sum game over time. Every year, CBO reestimates the baseline to determine expected costs. Baseline projections rise and fall based on changes in economic conditions, even without any action by Congress. For example, when the 2008 farm bill was enacted, the nutrition title was 67% of the five-year total. When the 2014 farm bill was enacted, the nutrition share had risen to 80% ( Table 2 ). This growth in size and proportion does not mean, however, that nutrition grew at the expense of agricultural programs. Legislative changes that are made in each farm bill account for only a fraction of the observed change between farm bills. Nutrition . Projected five-year SNAP outlays rose at an annualized rate of 13% per year from enactment of the 2008 farm bill to the 2014 farm bill. This $202 billion increase was entirely from changing economic expectations, since legislative changes in the 2014 farm bill scored a $3.2 billion reduction. Crop insurance. Projected five-year crop insurance outlays rose at an annualized rate of 11% per year from 2008 to 2014—nearly the same rate as SNAP, though smaller in dollars. The $20 billion increase was mostly from changing economic expectations rather than the $1.8 billion increase that was legislated in the farm bill. Farm commodity programs. Projected five-year farm commodity program outlays fell at an annualized rate of 9.1% per year between the 2008 and 2014 farm bills, given the $18 billion reduction that was scored from restructuring program payments. Following are summaries of the major provisions of each title of the 2014 farm bill. For more detailed information see CRS Report R43076, The 2014 Farm Bill (P.L. 113-79): Summary and Side-by-Side , which compares the provisions in the final 2014 farm bill to previous law and the House- and Senate-passed versions of the farm bill.