Sources and method
Primary sources first, and every date shown.
Where the figures and rules on this site come from, and how we handle them.
Primary sources first
Figures come from the agency that publishes them: INEGI (Mexico's statistics institute), Banco de México, the Secretaría de Economía, the SAT (Mexico's tax authority), IMSS (the social security institute), CONASAMI (the minimum-wage commission) and, on the USA side, the Census Bureau, USTR and U.S. Customs and Border Protection. Rules come from their official text: the Diario Oficial de la Federación (DOF) in Mexico and the Federal Register in the USA.
Two dates on every rule, one on every figure
A rule carries the date it was published and the date it takes force, because the two are often months apart. A figure carries the period it describes and the date we checked it.
When sources disagree
We show the range and name each source, rather than choosing one silently. Where no hard figure exists, the page says so and states what the conclusion rests on.
Secondary sources
Encyclopaedias, the press and industry reports help us find the primary source; Wikipedia, in English and in Spanish, is where many searches start. A figure that reaches a page is traced to its primary source or labelled as coming from the secondary one, with its date.
Reuse
You may quote from any page and share it, with a link to the page. Republishing a whole page needs our written permission. Each chart names its source; the source's own terms apply to its data.
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