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.