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Unit 3 — Economic Factors3.1 Monetary & Fiscal Policy3.1.4 Keynesian vs. Supply-Side Fiscal Policy

Keynesian vs. Supply-Side Fiscal Policy

🔑⚠️ FISCAL vs MONETARY POLICY — THE TOP TRAP IN THIS UNIT

Exam-relevance note the text makes: > “Both fiscal and monetary policy are used by the U.S. government to influence the economy. You’ll want to know how they differ, who controls them, and the main tools each one uses.

FISCAL POLICYMONETARY POLICY
🔑 Who controls itCongress (the House of Representatives and Senate) and the PresidentThe Federal Reserve
What it is / focuses on> “It focuses on how the federal government collects money (mainly through taxes) and how it spends that money.”Controls the money supply and, through it, interest rates
🔑 ToolsTaxation (how much revenue is collected, and how individuals and businesses are taxed) and government spendingDORM: Discount rate, Open market operations (repos / reverse repos, run by the FOMC), Reserve requirements, Margin requirements (Reg T)
In a recessionKeynesian: increase government spending, lower tax rates. Supply-side: decrease government spending and taxation to stimulateIncrease (loosen) money supply; bring interest rates down
In an inflationary environmentKeynesian: decrease government spending, raise tax ratesDecrease (tighten) money supply; bring interest rates up
Competing theoriesKeynesian (demand-side) theory; Supply-side theoryMonetarist theory (Fed’s actions are the most significant economic influence)

If a question mentions taxes or government spending → FISCAL → Congress/President.

If a question mentions the money supply, the discount rate, open market operations, reserve requirements, or Reg T → MONETARY → the Federal Reserve.

Do not attribute tax cuts to the Fed, and do not attribute reserve requirements to Congress.

Fiscal policy basics

“Fiscal policy is set and carried out by the U.S. Congress (the House of Representatives and Senate) and the President. It focuses on how the federal government collects money (mainly through taxes) and how it spends that money.”

ItemDetail from the text
Main source of government revenueTaxation — “Most government revenue comes from taxation. You’re probably most familiar with income taxes.”
IRS collections🔑 “The Internal Revenue Service (IRS) collected roughly $2.9 trillion in FY2025.”
Deficit spending🔑 “the federal government spent more than it collected, which is known as deficit spending
What fiscal policy determines“both how much tax revenue is collected and how individuals and businesses are taxed

Sidenote: The Internal Revenue Service (IRS)

🔑 The IRS performs the following roles on behalf of the federal government:

#Role
1Collecting taxes
2Providing assistance to taxpayers
3Investigating instances of tax fraud

“Investors pay close attention to the IRS because most investment returns are subject to taxation. Broker-dealers report these returns directly to the IRS on various tax forms. The investor then confirms this information when filing their own tax return. If an investor doesn’t file properly, they may be audited (investigated) and could face IRS enforcement actions.”

🔑 Lien vs levy — definitions

TermDefinition (word-for-word)Example
Lien> “A lien is a legal claim the IRS places on property to secure payment of a tax debt.”A claim securing an unpaid tax debt
Levy> “A levy is the legal seizure of property to satisfy that debt.”> “if an investor doesn’t pay capital gains taxes, the IRS may place a levy on the investor’s paycheck. This can result in part or all of the investor’s earnings being collected until the tax is paid.”

Trap: a lien is a claim; a levy is a seizure.

“The IRS is an agency of the U.S. Department of Treasury, the same organization responsible for issuing U.S. government debt securities.”

Sidenote: Progressive vs regressive taxes

TermDefinition (word-for-word)ExamplesKey figures
Progressive tax> “In a progressive system, higher income levels are taxed at higher rates.”Income taxes, estate taxes, gift taxes🔑 Lowest federal income tax bracket = 10% (for low reported income); highest bracket = 37% (for high reported income)
Regressive tax> “A regressive tax system applies the same tax rate regardless of income level or the amount of money involved.”Sales taxes, excise taxesFlat rate — “Whether you’re a billionaire or have no reported income, you pay the same percentage tax on items you buy at the store.”

Exam-relevance note the text makes: > “You don’t need to memorize the brackets, but it helps to know the range.”

Estate and gift taxes

TermDefinition / detail🔑 Threshold
Estate> “An estate is the assets owned by a deceased person, which are eventually distributed to heirs and beneficiaries.”The federal government taxes estates above $15 million
Gift taxProgressive, like estate taxThe federal government taxes gifts above $19,000

“In a progressive system, smaller amounts generally face lower tax obligations.”

Excise tax: > “Excise tax - a tax on a specific good (e.g., cigarette taxes) - is also regressive.”

Trap: sales and excise taxes are REGRESSIVE, not progressive, even though a wealthy person pays more dollars — the rate is the same.

Keynesian (demand-side) theory

TermDefinition / originCore idea
Keynesian (demand-side) theory> “developed by British economist John Maynard Keynes during the Great Depression era”🔑 > “The core idea is that increased government spending can drive economic growth.”

In a recession

  • Keynes argued that the government should spend large amounts of money.
  • “This spending increases demand for goods and services and can raise employment.”
  • “When the private (non-government) sector isn’t hiring or spending enough to support growth, the government can increase spending, including through deficit spending.”
  • Tax rates should fall “to encourage individuals and businesses to spend more, supporting growth.”

Example given: the American Recovery and Reinvestment Act of 2009, enacted during the Great Recession of 2008. “The bill led to more than $800 billion in spending on infrastructure, healthcare, education, and social programs during the most severe economic collapse since the Great Depression. More than a decade later, many economists agree the legislation reduced unemployment and encouraged economic growth.”

In an inflationary environment

  • “When inflation rises because the economy is ‘overheating,’ the government can reduce spending to help stabilize prices.”
  • “In an inflationary environment, the government should raise taxes to help stabilize prices.”

🔑 Keynesian response table

ConditionGovernment spendingTax rates
RecessionIncreasesFall
Inflationary environmentDecreasesRise

Supply-side theory

“In many ways, supply-side theory takes the opposite approach from Keynesian theory. As the name suggests, supply-side theorists focus on increasing the supply of goods and services across the economy, often through reduced taxation and reduced government spending.”

Example given: the Tax Cuts and Jobs Act of 2017, “which resulted in significant cuts to individual income, corporate, estate, and portfolio (investment) income tax rates.”

🔑 Demand-side vs supply-side

“When comparing supply-side and demand-side (Keynesian) theory, the key difference is what each view treats as the main driver of economic activity”

Demand-side (Keynesian)Supply-side
Main driver of economic activity> “Demand-side proponents emphasize demand for goods and services, including demand created by government spending.”> “Supply-side proponents emphasize production and investment by the private (business) sector.”
Government spendingIncreased gov’t spending benefits the economyDecreased gov’t spending benefits the economy
TaxationCut taxes in a recession; raise taxes during inflationReduced taxation stimulates the economy
Founder / example legislationJohn Maynard Keynes; American Recovery and Reinvestment Act of 2009Tax Cuts and Jobs Act of 2017

Summary of fiscal vs. monetary policy (the page’s own summary)

Fiscal policy

  • Controlled by Congress and the President
  • Keynesian (demand-side) theory
    • Increased gov’t spending benefits the economy
  • Supply-side theory
    • Decreased gov’t spending benefits the economy

Monetary policy

  • Controlled by the Federal Reserve
  • In a recession
    • Increase (loosen) money supply
    • Bring interest rates down
  • In an inflationary environment
    • Decrease (tighten) money supply
    • Bring interest rates up

Key points

Fiscal policy

  • Relates to taxation and gov’t spending
  • Controlled by Congress and the President

Internal Revenue Service (IRS)

  • Government agency responsible for:
    • Collecting taxes
    • Providing assistance to taxpayers
    • Investigating instances of tax fraud

Progressive tax systems

  • Higher taxes if more money involved
  • Examples:
    • Income taxes
    • Estate taxes
    • Gift taxes

Regressive tax systems

  • Flat tax rates
  • Examples:
    • Sales taxes
    • Excise taxes

Keynesian (demand-side) theory

  • Gov’t spending and taxation influence the economy
  • In a recession:
    • Gov’t spending increases
    • Tax rates fall
  • In an inflationary environment:
    • Gov’t spending decreases
    • Tax rates rise

Supply-side theory

  • Reduced gov’t spending and taxation stimulate the economy

Sources

Primary/official references for the material in this chapter. Every link was fetched and returned HTTP 200 on 2026-08-15.

#SourcePublisher
1Treasury’s role in markets and fiscal operations US Treasury
2GDP — definition, components, release schedule BEA
3The Fed Explained — structure, tools, functions Federal Reserve
4Achievable Series 65 — chapter 3.1.6 Achievable (course text)
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