All of the projected future growth in the federal budget will come from entitlements and interest costs

Two main factors are responsible for projected long-term growth in the federal budget: healthcare programs and interest payments. Federal healthcare spending is projected to almost double as a percent of GDP by 2040. The sharp rise in interest costs is a result of the continued accumulation of government debt, exacerbated by the rise in interest rates from their unusually low levels as the economy strengthens. On the other hand, with statutory limits on annually-appropriated spending in place through 2021, all other spending is projected to decrease as a percentage of GDP through the end of this decade before increasing to its average historical level for the long-term.