AHR999 index chart: Bitcoin price versus its 200-day DCA cost and a log-growth model. Below 0.45 = bottom-fishing zone, 0.45–1.2 = DCA zone, above 4 = overheated.
Left axis: BTC price (log). Right axis: AHR999 (log) with the 0.45 / 1.2 / 4 zones.
AHR999 = (price / DCA200) × (price / 10^(5.84 · log10(age in days) − 17.01))
The index multiplies two ratios: price against the average cost of buying a fixed dollar amount every day for 200 days (a geometric mean of closes), and price against a logarithmic growth model of Bitcoin's age. The commonly used zones are below 0.45 (bottom fishing), 0.45–1.2 (dollar-cost-average zone) and above 1.2 (wait). Coinfuty uses the published model coefficients and its own price series.
The index was designed for accumulation rather than tops: long stretches below 0.45 marked the 2015, 2018–19, 2020 and 2022 lows. For the hub, a reading of 4 or more — rare outside 2013, 2017 and early 2021 — counts as a peak signal.
0.52 as of Oct 19, 2026 — the DCA zone.
Below 0.45 is the bottom-fishing zone, 0.45 to 1.2 the dollar-cost-average zone, above 1.2 the zone where the original author suggested waiting. Coinfuty additionally treats 4 or more as a cycle-top signal on the hub.
As the geometric mean of the last 200 daily closes — the average cost of buying a fixed dollar amount each day. Coinfuty uses the geometric mean because it matches the published index; a harmonic mean gives values about 20% different.
Coinfuty computes every series on this page from daily BTC close prices and public constants — the Bitcoin halving schedule, block subsidy and published regression coefficients. Values refresh nightly (00:20 UTC) and the current day is patched hourly. These are historical, backward-looking indicators; nothing here is investment advice.