Statistics with a date and a source: our sourcing methodology

What this check measures

Every sentence in your main content that states a percentage, a multiplier ("3x", "twice as fast"), a large amount ("2 million"), a ratio ("1 in 5") or a dollar figure used as a fact. For each one we record whether it carries a date (a year, or a cue such as "as of 2025" in the same paragraph) and a source (a link in the same paragraph, or a named source such as "according to the IRS" or "(AICPA, 2025)"). Navigation, footers, price tables and forms are not read.

Why it matters

A number with a year and a source can be checked; a bare number has to be taken on trust. Google's helpful content guidance asks whether content presents information in a way that makes you want to trust it, such as clear sourcing, and whether it has easily verified factual errors. Bing's Webmaster Guidelines ask that content can be verified independently: facts explicit, key statements not relying on implied content. In a 2024 benchmark study of generative engines, adding statistics, quotations and citations were among the edits that most raised how often a source appeared in answers; that is a lab result on the authors' own setup, not a promise for live engines.

How we score it

When most of the numbers on a page carry neither a date nor a source, the finding is low severity, and medium for health, legal, tax and financing sites, where an unsourced number can move a real decision. It is our editorial methodology: it never exceeds medium, it can lower a pillar only up to a set limit, and it never takes the first action-plan slot while a measured defect exists. A page with no statistics is not assessed and never scored.

Confidence-flag rules

MEDIUM confidence. Statements are found by deterministic patterns over the main content, and sources are matched by link or by a named source phrase, so an unusual citation style can be missed. Every statement we judged is listed verbatim in the evidence so you can see exactly what we read.

Common mistakes

• Quoting an industry statistic with no year, so a reader cannot tell whether it is current.
• Citing "studies show" or "research shows" without naming or linking the study.
• Linking a source in a different section from the number it supports.
• Keeping a statistic after its source has been updated or withdrawn.

How to fix it

For each number, add the year it describes and link the original source in the same sentence or paragraph, ideally the primary publisher (a government agency, the standards body, the study itself) rather than an article that repeats it. Remove numbers you cannot source.

Primary sources

• Google Search Central, creating helpful, reliable, people-first content (last updated 2026-10-05, accessed 2026-10-07)

  Google Search Central

• Bing Webmaster Guidelines, "Ensure Content can be Verified Independently" (accessed 2026-10-07)

  Microsoft Bing

• Aggarwal et al., GEO: Generative Engine Optimization, KDD 2024, arXiv 2311.09735 v3 (2024-06-28, benchmark study, accessed 2026-10-07)

  arXiv

Changelog

• 2026-10-07 · First published. Pages with no numeric statements are reported as not assessed. Phone numbers, street addresses, ZIP codes, version numbers and dates are removed before we look for statistics.