Numbers of the week

October 5–11, 2026

2 videos published this week. Each one names its source and the period it covers.

Still frame from “Counting down the world's most polluted cities”

Counting down the world's most polluted cities

Public interest · Leaderboard

Still frame from “The world's 10 richest people, every year since 1987”

The world's 10 richest people, every year since 1987

Business and startups · Bar race

The week in one line each

01Counting down the world's most polluted cities13 of the 15 most polluted cities are in India or Pakistan.
02The world's 10 richest people, every year since 1987Today's 10th-richest person has more than 7× what the 1987 champion did (nominal dollars).