Mansfield relative strength
What it measures¶
Relative strength compares a share with a benchmark — for US shares, SPY, an exchange-traded fund (a fund whose units trade like a share) that tracks the S&P 500 index of 500 large US companies. The ratio is the share's weekly close divided by the benchmark's. Mansfield relative strength compares that ratio with its own average of the last 52 weeks:
Mansfield = (ratio ÷ 52-week average of the ratio − 1) × 100
Above zero, the share has been doing better against the market lately than over its past year; below zero, worse. It is named after Mansfield Charts, a British chart service that popularised it.
Why it is on the page¶
Stan Weinstein used a Mansfield reading above zero to confirm a Stage 2 advance: a rise that also beats the market. It is the Technical page's relative-strength figure and the single vote of the Price & timing strip's Relative strength tile.
Thresholds, their source and the population they were fitted on¶
| Zone | Mansfield | Strip vote |
|---|---|---|
| lagging | below −1 | not passed |
| in line | −1 to +1 | passed above 0, not passed below |
| leading | above +1 | passed |
- Source: the Mansfield formula as published by stage-analysis practitioners; Weinstein's zero line.
- Fitted on: no statistical sample for the formula; the momentum research behind relative strength is peer-reviewed and replicated.
- Evidence grade: practitioner convention.
A worked example¶
On weekly bars to 23 October 2026, against SPY: Apple +13.2 (leading), Honeywell International −8.1 (lagging). As the Technical page showed it on 9 August 2026, Celestica read +1.12 and rising — just above the in line band, agreeing with its Stage 2 reading.
What “No verdict” means here¶
The figure carries no verdict word. It needs a stored benchmark series and 52 weekly points of the ratio; without them the page and the strip say which is missing. For SPY itself it is not applicable.
What the verdict is and is not¶
The figure describes how the share has moved against the market compared with its own past year. It is not a forecast and not an instruction to trade the shares.