Research briefing
Canonical dataset release: corrected early returns and the 2021 low
- Written by
- The Bitcoin Data Guide editorial team
- Reviewed by
- Data review desk
- Dates
- Published 31 October 2026
Fact
Every figure in this briefing is drawn from the site's canonical dataset as it stood on 31 October 2026.
Forecast
Any forward-looking framing in this note is interpretation, not a measured outcome, and is labelled as such.
What changed since the previous briefing
This note follows Reading the halving-window record without overfitting it, filed on 30 September 2026. The sections below record what moved in the data or the research between the two dates.
What changed
Three full-year returns in the curated yearly table were corrected. 2010 now shows a gain of about 385 per cent, 2011 about 1,437 per cent and 2013 about 5,463 per cent, each measured from the year's opening price to its closing price. The 2021 yearly low was corrected to the January 2021 intraday low of about $28,130, which is the year's true low rather than the year's opening price. The corrected figures are the canonical values every published table, chart and article is derived from.
Why it matters
The early years of the record rest on a thinly traded market, so their annual extremes are widely cited reference points rather than exchange settlement prices. Stating the corrected returns against the year's open and close makes the basis of each figure explicit and keeps the derived rolling and holding-period series consistent with the table they are computed from.
What did not change
The 2012, 2014 through 2020 and 2022 through 2025 yearly figures are unchanged, as are the halving records, the drawdown records and the documented market extremes. The certification date on every dataset is unchanged, because the correction was applied to the same canonical release rather than to a new one.
Datasets this briefing draws on
- yearly-returns
- drawdowns
- market-extremes
Sources
- yearly-returns
- A curated dataset this briefing draws on.
- drawdowns
- A curated dataset this briefing draws on.
- market-extremes
- A curated dataset this briefing draws on.