Chapter 14 - Notes

14.1 - Macroeconomic Investment

Key Definition

Capital Stock and Depreciation

Three Types of Investment

1. Business Investment (largest category)

2. Inventories (smallest category)

3. Housing Investment

Why Investment Matters So Much

1. Investment drives the business cycle

2. Investment changes quickly but capital stock changes slowly

3. Investment drives long-term prosperity

14.2 - Tools to Analyze Investments

Core idea: Investment decisions involve costs today and benefits in the future. To compare them, you need tools to convert money between different points in time.

Tool 1: Compounding

Compounding formula:

Tool 2: Discounting

Discounting formula:

The two formulas are just inverses of each other:

Real vs Nominal Interest Rates in These Formulas

14.3 - Making Investment Decisions

Core Rule

How to Evaluate an Investment (Step by Step)

Step 1: Determine the up-front cost

Step 2: Forecast future revenues, accounting for depreciation

Step 3: Discount each year's revenue back to present value

Shortcut — The Valuation Formula:

Step 4: Compare PV of benefits to PV of costs

Alternative Perspective: The User Cost of Capital

Instead of evaluating the whole lifetime of an investment, you can ask: "should I buy this machine for just one more year?"

User cost of capital = the extra cost of using one more machine for one year

Decision rule: invest if next year's revenue > user cost of capital

Both approaches give the same answer:

Education as an Investment (important application)

14.4 - The Macroeconomics of Investment

The Real Interest Rate and Investment

Example of how interest rate matters:

Key Distinction: Movement Along vs Shift of the Investment Line

Investment Shifters

1. Technological Advances

2. Expectations

3. Corporate Taxes

4. Lending Standards and Cash Reserves

Summary Table

Factor Investment shifts RIGHT when... Investment shifts LEFT when...
Technological advances Better tech / lower depreciation —
Expectations Optimistic Pessimistic
Corporate taxes Lower taxes / tax breaks Higher taxes
Lending standards / cash Easier lending / more cash Tighter lending / less cash

And remember: real interest rate changes are movements ALONG the curve, not shifts.

14.5 - The Market for Loanable Funds

Supply is three buckets: Canadian households saving, the Canadian government saving (if it runs a surplus), and foreigners lending money to Canada

Key Setup

Supply and Demand Curves

Shifts in Supply of Loanable Funds (Three Shifters)

1. Changes in Personal Saving Rates

2. Government Budget Surplus or Deficit

3. Global Shocks / Foreign Saving

Shifts in Demand for Loanable Funds (Four Shifters)

These are the same four investment shifters from 14.4 — since investment = demand for funds:

  1. Technological advances → more productive capital → demand shifts right → higher interest rate
  2. Optimistic expectations → higher expected revenues → demand shifts right → higher interest rate
  3. Corporate tax cuts → businesses keep more revenue → demand shifts right → higher interest rate
  4. Easier lending standards / more cash reserves → demand shifts right → higher interest rate

Opposite direction for each → demand shifts left → lower interest rate

How to Analyze Any Scenario (3-Step Recipe)

  1. Does this affect saving (supply) or investment (demand)?
  2. Does the curve shift right (increase) or left (decrease)?
  3. What happens to the real interest rate and quantity of saving/investment?

Important Practice Scenarios from the Textbook:

Secular Stagnation

Questions

  1. We observe that the long-run interest rate has increased, and the equilibrium quantity of savings and investment has fallen. Which of the following changes would have caused this?
    An increase in the government budget deficit