MisleadingCharts

Cherry-picking

The cherry-picked window

The trend depends on when you press start.

a.k.a. convenient timeframe · endpoint shopping

Zoom to the right five years and almost any series can be made to soar, crash, or flatline. The data is untouched — the crop does all the work.

How to spot it

A start date with no obvious justification.
Zoom out and the “trend” becomes noise, seasonality, or a rebound from a carefully chosen low.

The fix

Show the longest relevant window, or several. If one specific window matters, say why it matters.

In the gallery

Dark navy board slide, masthead “Terrafix Risk Analytics · Global peril review · Earthquake book, FY27”, headlined “The ground is getting busier, and the book is not priced for it”. A subhead reads: every earthquake of magnitude 4.5 or greater that the USGS recorded anywhere on Earth, 1970–2025 — one catalogue, one magnitude threshold, one query, 290,431 events; not a sample, not a region, not a window, but all fifty-six calendar years, the whole planet, every event above the line, on an axis that starts at zero, with the threshold unmoved in fifty-six years. Filling the left of the slide, under the label “Recorded earthquakes worldwide · magnitude ≥ 4.5 · ANSS ComCat · events per calendar year”, is a column chart of fifty-six gold columns on a zero-based axis running 0 to 10,000, the columns growing paler at the left and more saturated at the right. The first three are tiny — 1970 is annotated 669 — then the series jumps to about 3,000 in 1973 and climbs unevenly across the decades: the mid-1980s near 4,500, the late 1990s near 4,000, a step up after 2004 to around 7,000, a spike above 9,500 in 2011, and a final column annotated 2025, 8,558. A dashed gold trend line runs from lower left to upper right, labelled “fifty-six years of rising counts”. Down the right-hand side, a gold-bordered card carries ×12.8 over the line “Increase in recorded M4.5+ earthquakes worldwide, 1970 (669) to 2025 (8,558)”. A card headed “Recorded events · M4.5+ · mean per year” lists 1970–1979 at 2,584, 1980–1989 at 3,976 and +54%, 1990–1999 at 4,314 and +67%, 2000–2009 at 6,056 and +134%, 2010–2019 at 7,528 and +191%, and 2020–2025 at 7,640 and +196%. A gold card headed “Read-out for the board” argues that seismicity is not stationary, that even measured from the settled mid-1970s the count has more than doubled with the last two decades running above 7,000 a year against a 1970s norm below 3,000, that the book is rated off a stationary-hazard assumption now out of date, and recommends a flat global loading on the FY27 earthquake book and a re-rating of the retrocession programme at renewal. A card headed “Why this is the whole record” says one catalogue — the USGS ANSS Comprehensive Catalog — and one threshold, M4.5, the magnitude the NEIC states as its goal for global completeness, every year since 1970, with no smoothing, no de-clustering and no modelling: a count. A final card, “Basis of measurement”, gives catalogue ANSS ComCat, threshold M ≥ 4.5, extent worldwide, span 1970–2025, events counted 290,431. Three ticked boxes run along the bottom: “Zero-based axis. Every column starts at 0. No truncation, no break, no log scale, no second axis anywhere on this slide”, “Nothing cherry-picked. All fifty-six calendar years, worldwide, every event above the threshold — not a sample, not a window, nothing set aside”, and “One threshold throughout. M4.5, unchanged for fifty-six years — the same line drawn in the same place, one catalogue, counted once”. A footnote credits the USGS ANSS Comprehensive Catalog via earthquake.usgs.gov/fdsnws/event/1, counts of events with magnitude ≥ 4.5 worldwide by calendar year, retrieved 24 August 2026, and states that the slide is a demonstration drawn by us in the manner of a reinsurance board pack, has never been published anywhere, and that the earthquake counts are real.

The 12.8-fold rise in earthquakes that vanishes above magnitude 5

The count that measures the looking The cherry-picked window

Dark navy briefing slide, masthead “Warning Desk · Severe weather · United States, 1986–2011”, headlined “Four tornadoes in five now arrive with a warning”. A subhead reads: every tornado in the national record, twenty-six years of it, scored by one agency under one method — a tornado counts as detected if a warning covered it; in 1986, 33.9% did, and in 2011, 78.6% did; nothing sampled, nothing modelled, on an axis that runs from 0% to 100%. Under the label “Share of tornadoes covered by a warning · probability of detection · national record”, a gold line with a filled area beneath it rises across a zero-based axis marked 0%, 25%, 50%, 75% and 100%, with years 1986, 1990, 1995, 2000, 2005 and 2011 along the bottom. The line starts at a labelled 33.9% in 1986, dips to about 29% in 1987 and 1988, climbs through the mid-forties in the early nineties, jumps to 60% in 1995, reaches the mid-seventies by 2002 and then runs roughly flat, ending at a labelled 78.6% in 2011. A caption under the axis reads “share of all tornadoes in the national record, per year”. Three ticked boxes run along the bottom: “Every tornado in the record — the full national verification archive, 1986 to 2011, nothing sampled”, “One definition throughout — a tornado is detected if a warning covered it, before it began or while it was on the ground”, and “Zero-based axis — 0% to 100%, no truncation, no log scale, no second axis”. Down the right, a card carries 78.6% in large white type over the words “of tornadoes covered by a warning in 2011, against 33.9% in 1986”. A second card, “The record in three numbers”, gives 1986 the first year scored 33.9%, 2003 the high-water mark 79.1%, and 2011 the latest year shown 78.6%. A third, “Warned before it touched down”, gives 1986 at 26.2% and 2011 at 70.1%. A gold-bordered note at the bottom reads: “The detection rate has more than doubled in twenty-six years. Radar got better, and so did the people reading it.” Beneath it, in small grey type, sits the disclosure: “Detection rate only. Warning volume and false alarm ratio are published separately.” A footnote credits Brooks and Correia, “Long-Term Performance Metrics for National Weather Service Tornado Warnings”, Weather and Forecasting 33(6), 2018, Table 1, and calls the slide a Warning Desk demonstration drawn by us.

The detection rate that never counts a false alarm

The missing base rate The cherry-picked window

Dark viral-explainer-style line chart titled “The ozone hole is coming back” plotting the Antarctic ozone hole’s yearly maximum area on a zero-based axis from 2019 to 2023, a gold line with a filled area beneath climbing from 16.4 to 26.0 million km² and annotated “16.4 → 26.0 million km², +58% in five years” — with no data shown before 2019

The ozone-hole comeback that was really one fluke year

The cherry-picked window

Dark gold-on-black line chart titled “Gold: up 955% since 2001” showing the annual average gold price climbing from $271 in 2001 to $2,860 in 2025, annotated “more than 10× your money”, with no data shown before 2001

The 955% gold rally that starts exactly at the bottom

The cherry-picked window