Methodology
The Bam-Index is an experimental signal tracking the flow of market wealth to Main Street. It estimates the value of the bottom half of the S&P 500 market cap per U.S. person, using public S&P 500 index levels and a transparent formula.
Formula
total_market_cap = SPX level × scaling factor (currently 10.56B)
bottom_half_cap = 10% of total market cap
Bam-Index per Person = bottom_half_cap / U.S. population (355M)
Sources
- SPX Weekly Close — Stooq (public data)
- Population estimate — U.S. Census Bureau (current projection)
Principles
- Public and transparent
- Replicable using openly available data
- No gated or proprietary datasets
- Designed to signal real shifts affecting small businesses
© Chuck Bambaren — Bam-Index 2025 🚀