S&P 500 Earnings Concentration: Are the Top 10 Backed by Profits?
The S&P 500 top 10 became more earnings-heavy between the two matched snapshots.
J.P. Morgan Asset Management reported the top 10 at 33.5% of S&P 500 market capitalization and 25.5% of trailing earnings in March 2024. By March 2026, those shares were 37.9% and 33.2%. Earnings concentration rose faster than market-cap concentration across those two endpoints.
Earnings concentration rose 7.7 points while market-cap concentration rose 4.4
Both observations come from the same J.P. Morgan Guide to the Markets chart family and use the same stated top-10 methodology. The comparison chart connects only the two labeled March endpoints.
Top-10 share of S&P 500 market cap and trailing earnings
Top-10 market-cap share increased from 33.5% to 37.9%. Top-10 trailing-earnings share increased from 25.5% to 33.2%.
| Snapshot | Top-10 market-cap share | Top-10 trailing-earnings share | Cap minus earnings | Earnings share / cap share |
|---|---|---|---|---|
| March 31, 2024 | 33.5% | 25.5% | 8.0 pp | 76.1% |
| March 31, 2026 | 37.9% | 33.2% | 4.7 pp | 87.6% |
The earnings share moved closer to the market-cap share
In March 2024, the top 10 held 33.5% of market capitalization but generated 25.5% of trailing earnings, an 8.0-point gap. By March 2026, that gap had narrowed to 4.7 points.
Another way to express the same arithmetic is that trailing-earnings share rose from 76.1% to 87.6% of the top 10's market-cap share. That is an increase of 11.5 percentage points.
Why this study does not publish the full 1996-to-2026 line
J.P. Morgan's charts show market-cap and earnings concentration back to 1996. The reviewed slides label the current endpoint, but they do not provide the intermediate monthly observations as a table in the material used here.
Rather than trace pixels from a chart and manufacture precision, the public dataset contains only the two exact labeled snapshots that can be checked directly. The longer history remains useful context, but it is not part of the downloadable Grizzly Bulls series.
For an exact long-run concentration reconstruction from published S&P DJI tables, see the 1965-2025 S&P 500 concentration study.
Methodology
- Retain the March 31, 2024 top-10 market-cap share of 33.5% and trailing-earnings share of 25.5% from the reviewed Guide to the Markets slide.
- Retain the March 31, 2026 top-10 market-cap share of 37.9% and trailing-earnings share of 33.2% from the same presentation family.
- For each snapshot, subtract earnings share from market-cap share to calculate the percentage-point gap and divide earnings share by market-cap share to calculate the descriptive coverage ratio.
- Compare the two endpoints. Do not assume the top-10 company membership is fixed between dates because the source reselects the 10 largest index companies.
- Do not digitize unlabeled monthly chart observations, infer fair value, or use this two-point comparison as a return forecast.
Reviewed sources
Download the matched snapshots
The CSV contains the two exact source endpoints plus derived gap and coverage metrics. The JSON adds methodology notes and source URLs. Neither file contains a digitized version of the publishers' monthly chart history.
Research data
- Download CSVCSVCSV downloadTabular public study data for spreadsheet analysis, independent checks, and new charts.Data snapshot March 31, 2026 · Reuse with attribution to the canonical study.
- Download JSONJSONJSON downloadStructured public study data for programmatic verification while preserving the published field names and research context.Data snapshot March 31, 2026 · Reuse with attribution to the canonical study.
Citation and reuse
When citing this study, describe the values as two matched J.P. Morgan Guide to the Markets snapshots. Do not describe the public CSV as the full 1996-to-2026 source series.