Open any newspaper's economy section and you'll meet the same three characters: how much the country produced (GDP), how prices are moving (inflation), and who has work (unemployment). This chapter teaches you to compute all three from raw tables, which happens to be exactly what the exam asks you to do.
Nothing in this chapter is "theory" yet. It's bookkeeping: learning what the scoreboard means before watching the game. If you can read a supermarket receipt, you can do everything in this lesson, and receipts are genuinely the right way to picture it. Keep that image; the whole chapter runs on it.
The definition, worth reading twice because half the concept questions hide in it:
GDP is the market value of all final goods and services produced within a country in a given period.
Each bolded phrase is a filter, and each filter is a potential exam question:
| Filter | What it excludes |
|---|---|
| market value | things without a price tag (chores at home, your own studying) |
| final goods | intermediate goods: the flour sold to the bakery doesn't count separately, the bread does (counting both would count the flour twice) |
| produced | pure asset swaps: selling a used car, or buying shares, produces nothing new |
| within a country / this period | production abroad; goods produced last year |
The same GDP can be counted from the spending side, and the exam's favorite identity splits spending by who spends:
Y = C + I + G + NX
consumption (households) + investment (firms buying capital, houses) + government purchases + net exports. Every euro of production ends up in exactly one bucket. There is no theorem to prove here; it's an accounting fact, like "income = spent + saved".
Here's the idea the whole chapter orbits. Suppose next year the country's receipts add up to 5% more than this year's. Did we actually make more stuff, or did the same trolley of stuff just get pricier? One number can't tell you. So economists print the receipt twice:
Watch it happen. Tiny economy, two goods, prices rise 5% from Year 1 to Year 2. Click the years:
"Nominal GDP increased" tells you nothing by itself about production: prices up, quantities up, or both, any of these raises it. (This exact statement is a real mock-exam question.) Real GDP is the one that tracks actual production.
Once you have both receipts, comparing them is free. Their ratio is a price index:
deflator = nominal GDPreal GDP × 100
Read it aloud: "how much more expensive is this year's stuff at this year's prices, compared to the same stuff at base-year prices?" In the base year, nominal = real, so the deflator is exactly 100. And then:
The inflation rate is just the percentage change of the deflator from one year to the next: π = (Dt − Dt−1) / Dt−1 × 100. One percentage-change move, the same one from Macro-00's math check.
In the widget above, Year 1's deflator is 210 / 220.5 × 100 = 95.24, Year 2's is 100, so inflation in Year 2 = (100 − 95.24) / 95.24 = 5%. That is exactly the 5% we baked into the prices. The machine works.
Question 1 of the mock exam is a three-good version of what you just did. Nothing new, just more rows. This trainer generates fresh tables forever; walk through the steps until it's boring, then answer without the steps.
On the real exam this question takes 3 or 4 minutes of careful arithmetic. That's fine. It's a guaranteed point that requires zero cleverness. Do it slowly, once, with the two-column habit you practiced here: nominal first, real second.
The Consumer Price Index answers a subtly different question: "how much more does the same shopping basket cost this year?" A statistics office (ISTAT in Italy) surveys what a typical household buys (so many pizzas, so many train tickets), freezes that basket of quantities, and sends someone out to reprice the identical basket every month:
CPI = cost of the basket at current prices ÷ cost of the basket in the base period × 100
Spot the mirror symmetry; it's the exam's favorite conceptual distinction:
| GDP deflator | CPI | |
|---|---|---|
| Quantities used | current year's production | frozen consumer basket |
| Covers | everything produced domestically (incl. machinery, exports) | only what consumers buy (incl. imports!) |
| An imported phone's price rise shows up in… | ✗ (not produced here) | CPI ✓ |
| A crane's price rise shows up in… | deflator ✓ | ✗ (households don't buy cranes) |
Deflator = what we Domestically produce. CPI = what we Consume. Both are "a ratio × 100", both turn into inflation via a percentage change.
The population splits like a family tree: working-age adults divide into the labor force (working or actively looking) and everyone else (students, retirees…). The labor force divides into employed and unemployed. Three ratios, three denominators. The entire difficulty of this topic is picking the right denominator:
| Ratio | Formula | Denominator |
|---|---|---|
| Unemployment rate | u = U / (E + U) | labor force |
| Participation rate | (E + U) / adult population | adult population |
| Employment rate | E / adult population | adult population |
The wrong options on the exam are always the same trick: a correct numerator over the wrong denominator (U over adult population, E over labor force…). Before computing anything, write LF = E + U in the margin. Then every ratio is one division.
| Nominal GDP | Σ quantity × current price |
| Real GDP | Σ quantity × base-year price |
| Deflator | nominal / real × 100 (= 100 in the base year) |
| Inflation | % change of a price index (deflator or CPI) |
| Real growth shortcut | ≈ nominal growth − inflation |
| u | U / labor force, LF = E + U |
| Participation | LF / adult population |
| Spending identity | Y = C + I + G + NX |
Eight lines. That's the entire formula load of course chapters 1–2.
Six questions in real exam style and scoring: +1 right, −⅓ wrong, 0 skip. Remember the strategy from Macro-00: certain → answer; clueless → skip; can eliminate one → guess.