What this shows: for each day, the Bitcoin price divided by the price 365 calendar days earlier (a ratio: 1.0 = flat year-over-year; below 1.0 = lower than 52 weeks ago — the latest reading is in the stats strip above). The blue line is the raw BTC price on the left log axis; the red line is the 365-day running ROI on the right log axis; the green dashed line marks y = 1 (break-even — red above it means BTC is higher than one year ago, below it means lower). Log axes let both the cents-era price and today's price sit on one chart, and make the ROI ratio readable across its full historical range (from ~0.1 in the deepest bear markets to hundreds of times in the 2011/2013/2017 cycles).

Data: daily BTC/USD market price from blockchain.info (free, no key). The price series begins when blockchain.info's daily record starts (July 2010); the ROI series begins one year later (July 2011), once a full 365-day anchor exists. Click any legend item to show or hide that series; drag to pan, shift+drag to box-zoom, scroll to zoom X, drag the Y-axis to zoom it, double-click to reset. Data may be revised.

Data: chart data (JSON) · source series (CSV) · blockchain.info market price