Safe Yield US core

Track records are simulated backtests, not live results. Methodology and current limitations: (1) Universe membership is real point-in-time index constituents - Nasdaq-100 (US) and WIG20 (PL), with dated add/drop history - so backtests see each index as it actually was, with no survivorship from later additions. Prices are adjusted close (total-return). When the backtest runs on the licensed, delisted-capable feed (EODHD), index members that later delisted or renamed are still priced and INCLUDED, closing the survivorship gap on the price side; when it runs on the keyless fallback feed, some delisted names are unpriced and dropped, which can flatter drawdowns. Two smaller residuals remain: the EU sleeve plus WIG20's most recent quarters are not yet point-in-time membership, and a few long-delisted tickers may still be unresolved. (2) Costs are charged per market on each rebalance's turnover - 5 bps for US names, 10 bps for EU, 20 bps for Warsaw (GPW) - the conservative end of typical half-spread-plus-fees for liquid names; market impact and FX conversion are not modelled (negligible at retail size, understated for large money). (3) Prices are total-return (dividends reinvested) where the data feed supports it. (4) Sharpe and Sortino use a flat 3%/yr cash (risk-free) rate, approximately the average US T-bill yield over the backtest window; actual cash rates varied 0-5% within it and Polish rates were mostly higher, so ratios are approximate. (5) Cross-market calendar gaps are bridged by carrying the last known price forward, which can modestly understate day-to-day volatility. (6) Rebalances are simulated at the same closing price the signal is computed from (close-to-close execution); a live follower trades at the next session's prices, so simulated results may differ from what next-bar execution would have produced. Past simulated performance does not predict future results.