Nearness-to-Range-Extreme Anchoring Momentum on XLMUSDT.BINANCE USD-M — Long-Short, Ungated, Pure Daily OHLCV: Hold ONLY While Price Sits in the Top/Bottom Decile of Its Trailing 180-Day Range, Flat Through the Whole Mid-Range

Hypothesis

A LONG-SHORT, single-instrument, pure-OHLCV strategy on XLMUSDT.BINANCE USD-M perpetual, DAILY bars. Signal is a LEVEL statistic, not a trailing return, moving average or dual-timeframe confluence: nh = (close - min180) / (max180 - min180). LONG while nh >= 0.90, SHORT while nh <= 0.10, FLAT in between (~70-80% of calendar time). Economic claim: reference-point anchoring / under-reaction at salient range extremes (George & Hwang 2004), which predicts drift exists ONLY at the extremes — the mid-range trend signal that always-in TSMOM and dual-TF confluence systems keep trading is noise that costs fees. No regime gate, no volume/volatility confirmation, no funding/OI/taker/sentiment feed, no vol-targeting. Declared degrees of freedom stated explicitly: venue (Binance USD-M, chosen for the 6.65-year daily span verified in catalog: 2020-01-21 → 2026-09-16, ~2430 bars), symbol (XLMUSDT — >=6y history, top-tier liquidity, zero prior use in 3161 experiments), window (180d), bands (0.90/0.10 entry, 0.55/0.45 exit).