Fundamental Analysis

September 18, 2026

Below is the full Convexa fundamental report for Friday, September 18, 2026, the most recent completed U.S. trading session.

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1. Main Fundamental Diagnosis

Friday’s session confirmed that the principal fundamental conflict in the U.S. equity market remains unchanged: corporate earnings continue to show strong momentum, while the cost of capital has once again approached critically elevated levels. The yield on the 10-year U.S. Treasury returned to 5.01%, while the 10-year real yield rose back to 2.68%, fully reversing the decline recorded in the previous session.

Macroeconomic data delivered the first meaningful sign of cooling in the manufacturing sector: manufacturing output unexpectedly declined by 0.3% in August after seven consecutive months of growth, whereas economists had expected a 0.3% increase. Total industrial production was unchanged. This does not yet indicate a broad economic contraction, but it suggests that expensive capital and elevated energy costs are beginning to transmit into the real economy.

Oil declined but remained above $100 per barrel, leaving the energy component of inflation materially elevated. Brent closed the session at $104.87.

The current fundamental configuration therefore consists of three elements: strong earnings, emerging weakness in selected parts of the economy, and an exceptionally high real cost of capital.

2. Fundamental Dashboard

The official U.S. Treasury yield curve shows a particularly important change on Friday: virtually the entire curve shifted higher. The 2-year yield rose from 4.67% to 4.76%, the 10-year yield from 4.94% to 5.01%, and the 30-year yield from 5.29% to 5.34%.

3. S&P 500 Earnings

Corporate earnings remain the most resilient component of the fundamental structure.

The latest confirmed S&P 500 third-quarter earnings estimate stands at $89.69 per share, compared with $88.64 at the end of June. The 1.2% upward revision differs materially from the normal seasonal pattern, as analysts have historically tended to reduce estimates during the first two months of a quarter.

The full-year 2026 earnings estimate was raised from $340.49 to $361.38 per share, an increase of 6.1%. Seven of the eleven sectors received upward revisions to their annual estimates.

No new aggregate data published on September 18 indicated a reversal of this trend.

4. Fundamental Earnings Breadth

On a full-year basis, earnings-estimate breadth remains reasonably broad, with upward revisions recorded in seven of the eleven sectors.

The quarterly picture is less evenly distributed. Only four sectors received upward third-quarter revisions, while seven experienced downward revisions. Energy recorded the largest increase, with its earnings estimate rising by 11.8%.

Accordingly, aggregate S&P 500 earnings are growing, but the breadth of that growth remains weaker than the headline aggregate figure suggests.

5. Market Valuation

For methodological consistency, the analysis uses the latest comparable FactSet figure: a forward price-to-earnings ratio of 19.1 as of September 11. A separate current estimate cited by Reuters on September 17 was approximately 20.3, but it is based on a different aggregation of earnings forecasts and therefore should not be combined with the FactSet series in the same calculation.

At a forward multiple of 19.1, the implied forward earnings yield is approximately 5.24%.

Market valuation in isolation is therefore lower than it was earlier in the year. Relative valuation versus bonds, however, remains extremely compressed.

6. Free Cash Flow

No reliable primary source provides a fresh aggregate daily free-cash-flow yield for the entire S&P 500 as of September 18.

The relevant issue therefore remains qualitative rather than artificially precise: the largest technology companies continue to combine strong earnings growth with exceptionally high capital expenditure on computing infrastructure.

FactSet research published Friday illustrates the scale of the artificial-intelligence investment cycle: artificial intelligence was mentioned on 331 of 493, or 67%, of S&P 500 second-quarter earnings calls. This was the third consecutive quarter in which the share exceeded 65%.

The quality of earnings growth therefore increasingly depends on how rapidly current investment spending begins to translate into sustainable free cash flow.

7. Equities Versus Bonds

This remains the principal weakness in the fundamental picture.

At a forward price-to-earnings ratio of 19.1:

forward earnings yield ≈ 5.24%.

The 10-year U.S. Treasury yield stands at:

5.01%.

The spread is therefore only:

approximately +0.23 percentage points.

In other words, the nominal yield on a government bond has once again moved very close to the forward earnings yield available from equities.

At the same time, the 10-year real yield rose from 2.61% to 2.68%.

This means that pressure on equities is coming not only through inflation, but through a higher real discount rate applied to future cash flows.

8. Credit Market

The corporate bond market continues to show no evidence of systemic financial stress.

The latest available investment-grade spread stands at 0.78 percentage points, unchanged from the previous session.

The high-yield spread also remained unchanged at 2.70 percentage points.

These data refer to September 17 because the series is published with a lag.

This remains one of the most important fundamental facts in the current market: the cost of government borrowing has risen sharply, but corporate credit risk has not shown a comparable deterioration.

9. Monetary Conditions

Following the September meeting, the Federal Reserve policy rate stands in a range of 3.75–4.00%.

By Friday’s close, the market assigned approximately a 55.4% probability to another rate increase at the October meeting, compared with 42.5% one week earlier and only 7.2% one month earlier.

The market is therefore gradually shifting from treating the September increase as an isolated move to pricing the possibility of a broader renewed tightening cycle.

The most important signal from Friday was the return of the 10-year Treasury yield above 5% alongside higher short-term yields.

10. Macroeconomy

Friday’s data delivered a mixed but important signal.

Total industrial production was unchanged in August after increasing by 0.2% in July. On a year-over-year basis, production rose by 1.4%.

Manufacturing output, however, declined by 0.3%, against expectations for a 0.3% increase. Motor vehicle and parts production fell by 1.2%, while computer and peripheral equipment production declined by 1.4%.

Capacity utilization remained at 76.3%, 3.1 percentage points below its long-run average.

The transmission mechanism is becoming increasingly visible:

expensive energy + high interest rates → higher costs → weaker manufacturing activity → lower future earnings growth in cyclical sectors.

For now, this process is only beginning to emerge.

11. Corporate Developments

Friday brought no corporate event capable of materially changing the aggregate S&P 500 earnings outlook.

The principal corporate issue remains the investment cycle surrounding artificial intelligence. Reuters noted that investors continue to assess the risk of slower development and capital expenditure, particularly in the semiconductor sector. At the same time, semiconductor shares recovered on Friday, supporting both the Nasdaq and the S&P 500.

For now, this represents a risk to future spending assumptions rather than an actual reduction in aggregate earnings estimates.

12. Fundamental Divergences

First divergence: corporate earnings continue to rise while the real cost of capital has again approached the highs of the current cycle.

Second divergence: manufacturing is beginning to show signs of slowing, while the labor market and consumer demand remain comparatively resilient.

Third divergence: government bond yields remain near multi-year highs, while corporate credit spreads remain low.

The third divergence is especially important because it indicates that the market is still undergoing a repricing of the cost of money rather than a deterioration in corporate balance-sheet quality.

13. What Matters Next

Today, September 19, the U.S. equity market is closed. The next trading session will take place on Monday, September 21.

On Monday at 14:30 Spain time, the Federal Reserve Bank of Chicago will release its National Activity Index for August. The previous July reading was −0.08, consistent with economic growth running slightly below its long-term trend.

The indicator is not normally a major market catalyst, but in the current environment it will be useful as a cross-check on Friday’s signal of weakening industrial activity.

At the start of next week, three variables will matter more than any single macroeconomic release:

whether the 10-year Treasury yield remains above 5%; whether oil remains above $100 per barrel; whether the market continues to price another Federal Reserve rate increase.

Reuters also notes that next week’s U.S. macroeconomic calendar is relatively light, which may increase the influence of Treasury yields, oil prices and Federal Reserve commentary.

14. Final Fundamental Assessment

Fundamental Market Health: 52 out of 100

Compared with the previous session, the fundamental assessment deteriorated modestly. The reason is not corporate earnings, where there was virtually no change.

The deterioration came through a renewed rise in nominal and real bond yields, the return of the 10-year yield to 5.01%, and the first signs of weakness in manufacturing output.

At the same time, the credit market remains orderly and earnings expectations remain strong. The fundamental environment therefore does not yet resemble a classic pre-recessionary episode.

The principal risk lies elsewhere: if yields remain above 5% while earnings revisions stop moving higher, the market will have very little remaining fundamental valuation cushion.

Fundamental Bias for the Next Session

Because today is Saturday, there is no current U.S. trading session. For the next session on September 21, the fundamental bias is assessed as neutral with a moderate negative tilt.

Analytical, rather than statistically derived, probabilities:

upside: 30%; sideways: 35%; downside: 35%.

The primary variables capable of changing this distribution before Monday’s open remain oil prices and U.S. Treasury yields.