Editorial policy

Articles are published by the editors of this site. A date at the top of a guide is the date of that guide. Dates inside the historical record are the dates of the sources.

A worked example states its inputs and the formula. Treat a count as the plant's rate only after the plant measures it. A price belongs in the case only when it comes from the plant's own source.

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The historical record cites the pages named there, accessed 14 October 2026. A 2014 news sentence is not a current offer.