The Structural Federal Deficit

Mandatory spending, rising net interest costs, and the mathematical reality of a $34.5 trillion national debt.

The United States government operates with a structural deficit. This means that even in times of full employment and economic expansion, federal outlays significantly exceed federal receipts. For Fiscal Year 2024, the Congressional Budget Office (CBO) projects a deficit of $1.5 trillion, representing roughly 5.3% of Gross Domestic Product (GDP).

Outlays: Where the Money Goes

Federal spending is broadly categorized into mandatory spending (dictated by existing law rather than annual appropriations), discretionary spending (determined by annual spending bills), and net interest on the public debt.

FY 2024 Projected Outlays ($6.5 Trillion)

Social Security ($1.45T) 22%
Health / Medicare / Medicaid ($1.75T) 27%
Defense Discretionary ($850B) 13%
Net Interest on Debt ($870B) 13%
Other Mandatory & Non-Defense ($1.58T) 25%

Data Source: Congressional Budget Office (CBO) Baseline Projections, Feb 2024.

Notice that mandatory spending and net interest account for nearly 75% of the entire federal budget. This severely limits the capacity of Congress to alter the fiscal trajectory through annual appropriations debates alone. Any meaningful deficit reduction necessitates addressing Social Security, Medicare, or broad-based tax increases.

The Interest Burden

As the Federal Reserve has raised interest rates to combat inflation, the cost to service the national debt has surged. The Treasury must refinance maturing debt at significantly higher yields. Net interest payments are projected to exceed $870 billion in 2024—surpassing the entire defense budget.

Receipts: Individual vs. Corporate

To fund these outlays, the federal government collects revenue primarily through individual income taxes and payroll taxes. Corporate income taxes make up a surprisingly small fraction of total receipts.

Revenue Source Projected FY24 (Billions) % of Total Receipts
Individual Income Taxes $2,504 50%
Payroll Taxes (FICA) $1,772 35%
Corporate Income Taxes $569 11%
Excise, Estate, Customs, Other $195 4%

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The Trust Fund Depletions

The Old-Age and Survivors Insurance (OASI) Trust Fund, which pays out Social Security benefits, is projected to be depleted by 2033. Under current law, once the trust fund is exhausted, benefits would be automatically reduced to match incoming payroll tax revenues (resulting in an estimated 21% cut to benefits).

Fixing the shortfall requires structural adjustments: increasing the payroll tax rate, raising the cap on taxable earnings, increasing the full retirement age, or altering the benefit formula.