Which environmental number do we trust too easily?

Environmental headlines are full of single numbers: a recycling rate, an emissions total, a count of plastic in the ocean, a "percentage of renewable energy". Numbers feel solid, but each depends on definitions that rarely make it into the headline: what counts as "recycled", whether something is measured where it is collected or where it ends up, which years are compared, and how much uncertainty surrounds the estimate.

We are asking you to pick one figure you often see quoted and tell us what it hides. A good answer would name the number, explain how it is defined and measured, say how uncertain it is, and describe a better way to report it.

The aim is not to dismiss environmental data. It is to learn to read it as carefully as we would read a financial statement.