BPM
Most of finance is theatre. BPM is the back room — a small collection of interactive instruments that make the slow, unglamorous arithmetic of long-term wealth visible. No tickers. No predictions. Just the math, played at speed.
The Instruments
Three Investors,
Half a Century
Daisy invests on autopilot. Lucy times every bottom perfectly. Ben buys every top. Watch fifty years of S&P 500 returns play out in nine seconds — and see how close mindless monthly investing comes to supernatural foresight.
The Order of Things
Two retirees, identical $1M nest eggs, identical income needs, identical fifteen years of returns. The only difference: one taps a separate Reserve in down years. Watch the catastrophic gap that opens when bad years strike early.
Twins, Apart
Benson saves $5,000/year for ten years, then stops forever. Ada saves $5,000/year for thirty years — three times more total. Same returns, same retirement age. Benson wins by 30%. The most expensive instinct in personal finance, dissolved.
The Cost of Flight
Two siblings inherit $100,000 in 2000. One holds through every drawdown. The other panics and sells after each crash, returning months later. By selling after each crash and missing the rebound, the panicker keeps half what the holder does.
The Inflation Eraser
Three savers, same $100,000, three vehicles, untouched for 30 years. Toggle between nominal and real purchasing power and watch the saver who feels safest quietly lose almost half her wealth — without anyone stealing a single dollar.
The Quiet Investor
Three people, same S&P 500 fund, same $100K, same thirty years. Tess panics after every loss. Sam holds steady. Fern forgot her password. The forgetter ties the steady hand. The active manager loses two-thirds of the wealth — by trying.
The Merchant's Paradox
Three merchants in St. Petersburg, 1738. Each year Boris bets full on one voyage. Hanna splits across two. Stefan stays in T-bills. Same expected return per ruble at risk for Boris and Hanna. After thirty years Boris ends with $5K, Stefan $18K, Hanna $27K. The arithmetic mean lied. The geometric mean told the truth.
Every instrument here exists to defeat one specific instinct that costs families money across generations. The first one — Three Investors — was built to retire the phrase "I'll wait for a dip." Each subsequent tool will target a single, stubborn, expensive belief about money.