#underwater

How far every major market is below its peak and how long it has been underwater, computed live from Yahoo Finance (no key, nothing stored). Drawdown is the risk investors actually feel: not volatility in the abstract, but the gap between today's price and the high-water mark, and the painful stretch spent climbing back. For every asset — equity indices, bonds, gold, oil, commodities, FX and crypto — this measures the current drawdown from its rolling peak, the worst (maximum) drawdown over the window, the date and level of the peak, how many days it has been underwater, and how much of the fall it has already recovered. The monitor endpoint returns the whole universe ranked by current drawdown — what is deepest underwater and what is back at new highs — with a summary of how many markets are in drawdown. The asset endpoint returns one market's drawdown card. The universe endpoint lists what is covered. The cross-asset drawdown / underwater-recovery cut — distinct from the FX-only drawdown API, the crypto all-time-high API and the cross-asset volatility API (which ranks risk-adjusted return, not the underwater curve). It answers how far from the highs, and how long.

api.oanor.com/assetdrawdown-api

Underwater-sound and sonar maths as an API, computed locally and deterministically — the speed, absorption and ranging numbers a marine engineer, sonar developer or oceanographer works with. The sound-speed endpoint gives the speed of sound in seawater from the Mackenzie nine-term equation: about 1,500 m/s — far faster than in air — rising with temperature, salinity and depth, so a profile of 25 °C, 35 ppt at 1,000 m gives 1,550.7 m/s. Because the speed varies with depth, sound rays bend and form the SOFAR channel that carries whale song and signals across whole oceans. The absorption endpoint gives Thorp's sound-absorption coefficient in dB per km against frequency, with the loss over a path: seawater swallows high frequencies fast, which is why long-range sonar and whale calls are low-pitched while high-frequency sonar gives sharp images only at short range. The echo-range endpoint turns an echo sounder's or sonar's two-way travel time into the range or depth — distance = sound speed × time ÷ 2 — so a one-second round trip at 1,500 m/s is a target 750 m away, its accuracy resting on the assumed sound speed. Everything is computed locally and deterministically, so it is instant and private. Ideal for sonar and hydrophone tools, marine-survey and bathymetry apps, ocean-acoustics research, and AUV/ROV navigation utilities. Pure local computation — no key, no third-party service, instant. Standard-equation estimates over their valid ranges. 3 compute endpoints. For the speed of sound in air and Mach use a Mach-number API; for decibels a sound-level API.

api.oanor.com/sonar-api