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Understand economics at your own pace: step-by-step guided courses, and exercises to practice.
🎓 47 guided courses🎯 10 exercise types🪜 7 steps per course
Your guided courses
📊GDP6
🏭GDPMeasuring a nation's output in a single number — and knowing where the line runs around what it counts.
GDP = C + I + G + (X − M)0 / 7 stepsStart 🧑🤝🧑GDP per capitaBringing a country's wealth down to one person.
GDP per capita = GDP / population0 / 7 stepsStart 🧮Nominal vs real GDPTelling a rise in prices apart from genuine growth.
Real GDP = nominal GDP / deflator × 1000 / 7 stepsStart 🔭The three approaches to GDPThree routes through the accounts, one and the same result.
Output = Expenditure = Income0 / 7 stepsStart 🧪Growth accountingAssigning observed growth to its drivers — and reading honestly the residual that remains.
gᵧ = α·g_K + (1−α)·g_L + g_A0 / 7 stepsStart 📈Inflation5
📈InflationWhen money loses a little of its purchasing power every year.
π = (CPI_t − CPI_t−1) / CPI_t−1 × 1000 / 7 stepsStart 🔥The causes of inflationDemand, costs, money: where do price rises really come from?
M·V = P·Y0 / 7 stepsStart 🛒Inflation and purchasing powerWhen prices rise, the same money buys less.
purchasing power = income / price level0 / 7 stepsStart 🧊What is deflation?When prices fall durably — and why that is not good news.
change in prices = (price_now − price_before) / price_before × 1000 / 7 stepsStart 🎚️The expectations-augmented Phillips curveDoes the inflation-unemployment trade-off really exist? Short run versus long run.
π = πᵉ − α·(u − u*) + ε0 / 7 stepsStart 👷Unemployment4
📐Measuring unemploymentBehind the single rate, who is really being counted?
unemployment rate = unemployed / labour force × 1000 / 7 stepsStart 🧩Types of unemploymentNot all unemployment is alike — and none of it is cured the same way.
total unemployment = frictional + structural + cyclical0 / 7 stepsStart 🎯Equilibrium unemployment (NAIRU / WS-PS)The one unemployment rate that does not make inflation accelerate — where the wage wanted meets the wage tolerated.
u* = (b + µ) / α0 / 7 stepsStart 📉Financial markets5
📈Return and riskEvery hoped-for gain is paid for in accepted uncertainty.
R = (P₁ − P₀ + income) / P₀ × 1000 / 7 stepsStart 🪙Bond prices and interest ratesWhy a bond loses value when rates go up.
Price = Σ coupon / (1 + r)ⁿ + face / (1 + r)ᴺ0 / 7 stepsStart 🪙Share or bond?Become a co-owner of a company, or lend it money?
R = (P₁ − P₀ + income) / P₀ × 100 — for BOTH securities0 / 7 stepsStart 📉How does the stock market work?Not one market, but a set of them — where a price settles no scarcity of the day, but a bet on the future.
capitalisation = number of shares × price0 / 7 stepsStart 🧮Valuing a share: the Gordon-Shapiro modelWhat is a share worth? The discounted sum of all its future dividends.
P = D₁ / (r − g)0 / 7 stepsStart 🏦Monetary policy5
🏦The policy rate and transmissionHow a single ECB decision changes the price of money everywhere.
↑ policy rate → ↑ loan rates → ↓ demand → ↓ inflation (1 to 2 years)0 / 7 stepsStart 💶The money multiplierWhere the textbooks' 1/r comes from — and why it is a ceiling, never a forecast.
ceiling: m = 1/r · observed: m = (1 + c)/(c + e)0 / 7 stepsStart 🏦What is a central bank?The keeper of prices, who makes credit dearer or cheaper.
annual interest = amount borrowed × rate0 / 7 stepsStart 🐖Do your savings beat inflation?Your account pays interest… but does it really make you richer?
real return ≈ nominal rate − inflation0 / 7 stepsStart 🧮The Taylor ruleWhat if a simple formula told the central bank where to set its policy rate?
i = r* + π + 0.5(π − π*) + 0.5·GDP gap0 / 7 stepsStart 🏛️Fiscal policy5
💸The fiscal multiplierWhy €1 spent by the state can return more than €1 of GDP — but rarely as much as people say.
ΔY = k × ΔG, with k = 1 / (1 − c)0 / 7 stepsStart ⚖️Deficit and the public balanceOne word, several numbers: which deficit are we talking about, and how does it become debt?
Balance = Revenue − Spending; Debt₁ = Debt₀ + Deficit0 / 7 stepsStart 🏛️Where does the state's money come from?Who pays, at which till — and why a rate alone never says what a tax brings in.
revenue = base × rate0 / 7 stepsStart 🏛️Where does the state's money go?The real amounts item by item — and why public spending is endured more than it is decided.
spending = beneficiaries × average amount0 / 7 stepsStart ❄️The dynamics of public debtWhen does debt run away on its own — and when is growth enough to contain it?
Δb = (r − g)/(1 + g) · b − s0 / 7 stepsStart 🌍International trade4
⚖️The trade balanceWhat it really counts, what it leaves out — and why a deficit is not a debt.
trade balance = exports − imports0 / 7 stepsStart 🤝Comparative advantageWhy a country better at everything still needs the others — proved in figures.
opportunity cost = what is sacrificed ÷ what is obtained0 / 7 stepsStart 💱What is an exchange rate?The price of one currency in another: where that number comes from, and why its direction of reading catches everyone out.
price in $ = price in € × rate ($/€)0 / 7 stepsStart 🧭The real exchange rate and PPPThe board at the bureau de change does not say whether a country is expensive: here is the number that does.
q = e × P / P* (= e / e_PPP)0 / 7 stepsStart ⚖️Aggregate supply & demand5
🛒Aggregate demandThe same formula as GDP — but it does not say the same thing, and that is the whole point.
AD(P) = C(P) + I(P) + G + (X − M)(P)0 / 7 stepsStart ⚡Shocks and AS-AD equilibriumOne rule that replaces four cases to memorise: where inflation, recession and stagflation come from.
at equilibrium: aggregate demand = aggregate supply0 / 7 stepsStart ⚖️The law of supply and demandTwo relations, a single price — and the distinction almost everyone misses: sliding along a curve, or shifting it.
Qd(P*) = Qs(P*) → the pair (P*, Q*)0 / 7 stepsStart 🔄Why do prices change?What moves a price, by how much — and why a price that rises is not inflation.
P* such that Qd(P) = Qs(P)0 / 7 stepsStart 🎯Price elasticity and tax incidenceWho really pays a tax? Neither the one who hands it to the revenue service nor half each — and it can be proved.
share borne by the consumer = εs / (εs + εd)0 / 7 stepsStart 🐖Saving & investment4
🐖The saving rateWhy a country can save more and more… without its saving rising.
saving rate = (disposable income − consumption) / disposable income0 / 7 stepsStart 📈Compound interestWhy 30 years at 5% earn you not €1,500 but €3,322 — and where the difference is made.
C_final = C × (1 + t)^n0 / 7 stepsStart 🏦Where to put your savings?The right home for your money does not depend on the highest advertised rate, but on the date you will need it.
equivalent gross rate = net rate / (1 − tax)0 / 7 stepsStart 🏗️The Solow model: saving and the steady stateWhy a country that saves twice as much does not grow twice as much — and why saving 70% makes you poorer.
Δk = s·f(k) − (n + δ)·k0 / 7 stepsStart 💵Money & banking4
🏦Money creationThe two lines written on a bank's balance sheet when it grants you a loan.
money created = new loans − repayments0 / 7 stepsStart 💶The functions and aggregates of moneyWhat an asset must still be able to do to be counted as money.
M1 ⊂ M2 ⊂ M3 — and the border is at 2 years0 / 7 stepsStart 🔄Why money? The barter problemTwo obstacles, one single product: what a world without a common unit costs.
barter: n(n − 1)/2 prices to display, n(n − 1) meetings to make0 / 7 stepsStart 🪙The quantity theory of moneyWhy printing money ends up, in the long run, raising prices — not output.
M·V = P·Y → π ≈ g(M) − g(Y)0 / 7 stepsStart