GEM: Dual Momentum Tracker

GEM Calculator is a free investment signal app that implements the Global Equity Momentum (GEM) strategy — a proven dual-momentum approach developed by Gary Antonacci to help investors decide between US stocks, international stocks, and safe assets like Treasury bills. Stop guessing. Get a clear, data-driven monthly signal telling you exactly what to hold. HOW IT WORKS The GEM strategy uses two simple rules every month: 1. Safety Check — Is the US stock market trending up or down? If down, move to safe assets. 2. Pick the Winner — If markets are trending up, compare US vs international stocks and hold whichever has stronger 12-month momentum. That's it. One decision per month. No day trading, no complex analysis. MONTHLY INVESTMENT SIGNAL Open the app and instantly see this month's signal: • LONG SPY — Hold US equities • LONG VEU — Hold international equities • CASH BIL — Move to Treasury bills (risk-off) The signal includes a buffer indicator showing how far the market is from a trend reversal, plus a countdown to the next monthly update. BACKTEST & PERFORMANCE TRACKING Don't just trust the strategy — verify it: • Full historical backtest with Dollar-Cost Averaging (DCA) simulation • Compare GEM returns vs Buy & Hold across 1, 2, 3, and 5-year periods • Maximum drawdown analysis for both strategies • Month-by-month detailed log of every signal and portfolio change • Interactive performance charts for all three asset classes CUSTOMIZABLE ETF SELECTION Tailor the strategy to your broker and region: • Choose from 30+ ETFs for each asset slot • US Equities: SPY, VOO, IVV, QQQ, and more • International Equities: VEU, VXUS, EFA, EIMI.L, AMUN.PA • Safe Assets: BIL, SHV, SGOV • Non-US listed ETFs supported for European and global investors SMART NOTIFICATIONS Never miss a signal change. Enable monthly reminders on the 1st of each month so you always know when to check your portfolio allocation. GEM PRO Upgrade to Pro for the full experience: • Monthly signal alerts pushed to your device • Extended backtest history up to 5 years • Custom ETF watchlist • Priority updates and new features WHO IS THIS FOR? • Passive investors who want a systematic, rules-based approach • Index fund investors looking to reduce drawdowns • Momentum strategy enthusiasts • Anyone tired of emotional investing decisions GEM Calculator is an educational tool. Past performance does not guarantee future results. Always do your own research before making investment decisions.