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Chart topics: seven corners of real data

Extraplot's chart bank covers seven kinds of data. Each has its own habits, its own traps and its own kind of surprise. Pick a corner and learn how it moves.

A chart is a question with a shape. The shape depends on what is being counted. A country's fertility rate, a baby name's share of births, a Wikipedia article's yearly pageviews and the price of a flat in London all produce lines — but they behave so differently that guessing them well requires different instincts.

Extraplot's chart bank is organised into seven categories for that reason. A daily set never repeats a category, and never contains more than one name chart or one search chart, so a day's five charts are five genuinely different questions about the world. The pages below explain what each category is made of, where its charts come from, and how to draw its kinds of line.

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The seven categories

Each page covers the data angle, example questions and scoring advice.

How the mix works

A day of five charts, five different questions

The scheduling rules are simple and deliberately strict. Each day has five slots: two warm-ups, two medium charts and one hard chart. No category appears twice in one day, and at most one chart comes from the names category and at most one from search. That means a typical day might pair a country's electricity access with a baby name, a Wikipedia spike, a format's decline and a price series — five different kinds of reasoning in five minutes.

Across the season, the balance stays roughly steady rather than clustering: country data is the largest group, followed by search and names, then nature, tech, culture and money. The aim is variety you can feel from one day to the next, not a quota that makes every set predictable.

Why it matters

Category knowledge is guessable skill

After a few weeks, most players notice they are better at some categories than others. Someone who reads a lot of news guesses country data well and falls apart on baby names. Someone who works in tech over-extrapolates adoption curves. That asymmetry is the learning: the archive lets you play a category deliberately, and the reveal note tells you the mechanism you missed.

  • Start with the category you are worst at, not the one you enjoy.
  • Read the unit before drawing: a share, a count and a price have different ceilings.
  • On search charts, expect spikes; on nature charts, expect slow drift.
  • Names charts are about peaks; culture charts are about collapses; money charts are about reversals.

Next

One chart from each corner.

Five charts a day, drawn from all seven categories. Free, no sign-up.

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