# Monetary Policy

Business I · Introduction to Economics · https://tryals.app/learn/business-i/monetary-policy

## The Economy's Thermostat

**Monetary policy** is the central bank's management of interest rates and the money supply to keep inflation low and output stable. In the euro area, the **European Central Bank (ECB)** targets an inflation rate near 2%.

**The main lever: the policy interest rate**, the rate at which commercial banks borrow from the central bank. It ripples outward: bank funding costs → loan and mortgage rates → spending and investment.

| Stance | When to Use | Action | Economic Chain |
| --- | --- | --- | --- |
| **Expansionary** | Economy weak, inflation low | Cut policy rate | Cheap credit → spending rises |
| **Restrictive** | Inflation high | Raise policy rate | Dear credit → demand cools |

## Mechanics & Limits

**How banks multiply money.** Banks keep a fraction of deposits as reserves and lend the rest. With reserve ratio $r$, the **money multiplier** is $\frac{1}{r}$. A 10% ratio turns 1,000€ into up to 10,000€ in total deposits.

**Transmission lags.** Policy changes reach prices only after **6–24 months**, so central banks steer by forecast. **Expectations** of future policy move markets before the actual rate change hits.

**Common pitfall:** Treating the multiplier $\frac{1}{r}$ as a strict prediction. It is an upper bound; if banks hold excess reserves or borrowers stay away, actual money creation falls short.

## Practice questions

7 of this lesson's 13 practice questions, with answers. The full set is in the app.

### 1. Order the transmission of a rate cut from decision to prices.

**Answer:**

1. Central bank lowers the policy rate
2. Banks cut loan and mortgage rates
3. Households and firms borrow and spend more
4. Aggregate demand and output rise
5. Price pressures build with a long lag

**Why:** Decision → credit → spending → output → prices: each link adds months, so the chain’s far end arrives up to two years late.

Page: https://tryals.app/practice/business-i/monetary-policy/order-the-transmission-of-a-rate-cut-from-decision-to-prices

### 2. Sort each situation by the monetary policy it calls for.

**Answer:**

- Cut rates (expansionary): Deep recession, inflation near zero, Unemployment surging, firms postponing investment, Deflation: prices falling, spending frozen
- Raise rates (restrictive): Inflation at 8% and accelerating, A credit-fueled housing bubble inflating fast

**Why:** The thermostat rule: too cold (recession, deflation) → cheaper money; too hot (inflation, bubbles) → dearer money.

Page: https://tryals.app/practice/business-i/monetary-policy/sort-each-situation-by-the-monetary-policy-it-calls-for

### 3. Match each link of the transmission chain to its description.

**Answer:**

- Policy rate → The central bank’s price for lending to banks
- Bank lending rates → What firms and households actually pay
- Aggregate demand → Spending that responds to credit conditions
- Inflation → The final target, reacting after long lags

**Why:** Policy rate → market rates → spending → prices: each arrow takes months, which is why policy steers by forecast.

Page: https://tryals.app/practice/business-i/monetary-policy/match-each-link-of-the-transmission-chain-to-its-description

### 4. Why do central banks act on _forecasts_ of inflation rather than waiting for inflation to appear?

A. The law forbids reacting to current data
B. Waiting would require larger money printing
C. Forecasts are more accurate than measurements
D. Rate changes take 6–24 months to affect prices

**Answer:** D. Rate changes take 6–24 months to affect prices

**Why:** Transmission lags mean today’s rate decision lands on next year’s economy. React only to current inflation and you are always fighting the previous war, usually overcorrecting into the next one.

Page: https://tryals.app/practice/business-i/monetary-policy/why-do-central-banks-act-on-forecasts-of-inflation-rather-than

### 5. A central bank cuts rates to zero and the economy still stagnates. Why does the tool lose its grip there?

A. Because fiscal policy always dominates monetary policy in a recession
B. Because banks stop lending when rates are low and margins thin
C. Because low rates cause inflation, which cancels the stimulus
D. Nominal rates cannot fall far below zero without cash hoarding

**Answer:** D. Nominal rates cannot fall far below zero without cash hoarding

**Why:** Cash pays zero and cannot be taxed away easily, so it sets a floor beneath which rate cuts stop transmitting. That constraint is exactly why quantitative easing and forward guidance were invented after 2008, and why the debate about fiscal policy came back after decades of quiet.

Page: https://tryals.app/practice/business-i/monetary-policy/a-central-bank-cuts-rates-to-zero-and-the-economy-still-stagnates

### 6. Which effects follow a central-bank rate _cut_, all else equal?

A. Investment projects on the margin become viable
B. Mortgages and business loans get cheaper
C. Aggregate demand strengthens
D. The money multiplier mechanically falls

**Answer:** A. Investment projects on the margin become viable; B. Mortgages and business loans get cheaper; C. Aggregate demand strengthens

**Why:** Cheaper credit feeds spending and investment. The multiplier depends on reserve behavior, not directly on the policy rate.

Page: https://tryals.app/practice/business-i/monetary-policy/which-effects-follow-a-central-bank-rate-cut-all-else-equal

### 7. Banks hold a 25% reserve ratio. Set the slider to the money multiplier.

**Answer:** 4 (within ±0.3)

**Why:** $1/0.25 = 4$: each euro of base money supports up to four euros of deposits. Tighten the ratio and the same base carries less money, the quiet lever behind the loud one.

Page: https://tryals.app/practice/business-i/monetary-policy/banks-hold-a-25-reserve-ratio-set-the-slider-to-the-money