Sandpone — S&P 1 Strategy Tracker

Every quarter, check who holds the #1 spot in the S&P 500 by market cap. If the throne changed, sell everything and rotate fully into the new leader. Otherwise, hold.

Why it might work

Momentum at scaleThe most valuable company is usually mid-cycle in the dominant technology era of its time. Owning it is a bet that leadership persists.

Forced disciplineThe rule is mechanical. You hold until the market says otherwise — no forecasts, no judgement calls, nothing to second-guess.

Concentration cuts both waysDiversification caps the upside. One company compounding faster than the average will beat the index — if you are holding the right one.

What the record actually shows

Rotation timing dominates everythingThis is the big one, and it is measured, not theorised. Checking quarterly caught 15 throne changes since 2001 and returned —. The same rule on the same companies, judged over multi-year leadership instead, gives roughly $265,000. Each extra rotation sells a winner and buys a peak.

Tax drag is severeEvery rotation fully liquidates, so every rotation is a taxable event. In a taxable account the same record returns —. This strategy belongs in a sheltered account or not at all.

Concentration riskYou own exactly one stock. A single scandal or earnings miss hits the whole portfolio, with nothing to cushion it.

Not investment advice. Sandpone is a public record of a mechanical rule set, published for discussion and curiosity. Nothing here is a recommendation to buy or sell any security.

Backtested, not traded. Everything before this site existed is reconstructed from historical data with the benefit of hindsight about which company held the top spot. No money was invested on these terms. Returns are pre-tax and ignore commissions, spreads, and the capital gains due on every rotation — a full liquidation each time, so that drag is material.

Provenance. Prices and dividends from Yahoo Finance; inflation from BLS series CUUR0000SA0; share counts for the leaderboard from SEC XBRL, which begins in 2009. Every figure is computed by ingest.py and leaderboard.py in the project repository and stored as fetched — the page renders those records and calculates nothing of its own. Nothing here is interpolated: a missing input renders as a gap.

Rotation dates are not yet verified. The companies and their order reflect the throne history in outline, but the specific quarter of each hand-over has not been confirmed against a primary source. Every rotation on this page is therefore marked unverified, its quarters are shaded, and the headline figures stay blank. Treat the series as a working reconstruction, not a record.

Leaderboard coverage. Ranking is computed within a fixed candidate list of large-cap index members, not all 500. Companies whose share count cannot be resolved from unsegmented SEC XBRL — some multi-class issuers report only one class — are excluded outright rather than ranked on a partial count.

What the short forms mean

S&P 500: Standard & Poor's 500. A list of about 500 of the largest public companies in the United States, used as shorthand for "the US stock market".
S&P 1: The name of this strategy. Instead of owning all 500 companies, you own only the single most valuable one.
Market cap: Short for market capitalisation: what a whole company is worth, worked out as its share price times the number of shares that exist.
Roth IRA: Individual Retirement Arrangement. A US retirement account where your investments grow without being taxed, so nothing is deducted when you buy and sell inside it.
Taxable account: An ordinary investment account. Selling at a profit creates a tax bill, which is why this line ends up lower than the Roth IRA line.
Dividend: A cash payment some companies make to shareholders. Here they are always treated as being used to buy more shares.
Total return: Everything you made: the change in share price plus dividends, not just the price.
Quarter (Q1–Q4): A three-month block of the year. Q1 is January to March, Q2 April to June, Q3 July to September, Q4 October to December.
CAGR: Compound annual growth rate. The single yearly rate that, compounded, turns the starting amount into the ending amount — the fair way to compare periods of different lengths. A 25-year gain of 8.8% a year is not the same as 8.8% once.
YTD: Year to date. From the start of this calendar year until now.
CPI: Consumer Price Index. The standard measure of how much prices have risen, used here to express older dollars in today's terms.
BLS: Bureau of Labor Statistics. The US government agency that publishes the CPI.
SEC: Securities and Exchange Commission. The US regulator that public companies file their financial reports with.
XBRL: The machine-readable format those SEC filings use, which is how the share counts on this page are collected.
Ticker: The short code a company's stock trades under — NVDA is NVIDIA, AAPL is Apple.
Rotation: The moment a new company becomes the most valuable, so this strategy sells what it owns and buys the new leader.