Delta Air Lines (STU:OYC) E10: €0.40 (As of Jun. 2026)

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STU:OYC Delta Air Lines Inc STU:OYC
84 GF Score
Price €70.43
GF Value €50.39
Valuation Significantly Overvalued
! 5 Warning Signs
View Full Analysis

What is Delta Air Lines E10?

Delta Air Lines STU:OYC +1.41% 84 E10 is €0.40 as of Jun. 2026. GuruFocus rates STU:OYC with a GF Score™ of 84/100 and a GF Value™ of €50.39 (Significantly Overvalued). The stock has 5 warning signs investors should review.

E10 is a concept invented by Prof. Robert Shiller, who uses E10 for his Shiller P/E calculation. E10 is the average of the inflation adjusted earnings of a company over the past 10 years.

Delta Air Lines's adjusted earnings per share data for the three months ended in Jun. 2026 was €0.353. Add all the adjusted EPS for the past 10 years together and divide 10 will get our e10, which is €0.40 for the trailing ten years ended in Jun. 2026.

During the past 12 months, Delta Air Lines's average E10 Growth Rate was -4.20% per year. During the past 3 years, the average E10 Growth Rate was -2.00% per year. During the past 5 years, the average E10 Growth Rate was -0.10% per year. Please click Growth Rate Calculation Example (GuruFocus) to see how GuruFocus calculates Wal-Mart Stores Inc (WMT)'s revenue growth rate. You can apply the same method to get the E10 growth rate using E10 data.

During the past 13 years, the highest 3-Year average E10 Growth Rate of Delta Air Lines was 60.80% per year. The lowest was -88.20% per year. And the median was -6.25% per year.

As of today (2026-08-23), Delta Air Lines's current stock price is €70.43. Delta Air Lines's E10 for the quarter that ended in Jun. 2026 was €0.40. Delta Air Lines's Shiller PE Ratio of today is 176.08.

During the past 13 years, the highest Shiller PE Ratio of Delta Air Lines was 396.14. The lowest was 24.29. And the median was 91.55.


Delta Air Lines  (STU:OYC) E10 Explanation

If a company grows much fast than inflation, E10 may underestimate the company's earnings power. Shiller PE Ratio can seem to be too high even the actual P/E is low.

For the Shiller P/E, the earnings of the past 10 years are inflation-adjusted and averaged. The result is used for P/E calculation. Since it looks at the average over the last 10 years, the Shiller P/E is also called PE10.

The Shiller P/E was first used by professor Robert Shiller to measure the valuation of the overall market. The same calculation is applied here to individual companies.

Delta Air Lines's Shiller P/E Ratio of today is calculated as

Shiller PE Ratio=Share Price/E10
=70.43/0.40
=176.08

* For Operating Data section: All numbers are indicated by the unit behind each term and all currency related amount are in USD.
* For other sections: All numbers are in millions except for per share data, ratio, and percentage. All currency related amount are indicated in the company's associated stock exchange currency.

During the past 13 years, the highest Shiller P/E Ratio of Delta Air Lines was 396.14. The lowest was 24.29. And the median was 91.55.


Be Aware

Shiller PE Ratio works better for cyclical companies. It gives you a better idea on the company's real earnings power.


Delta Air Lines E10 Related Terms


Delta Air Lines E10 Historical Data

* Premium members only.

The historical data trend for Delta Air Lines's E10 can be seen below:

* For Operating Data section: All numbers are indicated by the unit behind each term and all currency related amount are in USD.
* For other sections: All numbers are in millions except for per share data, ratio, and percentage. All currency related amount are indicated in the company's associated stock exchange currency.

Delta Air Lines E10 Chart

Delta Air Lines Annual Data
Trend Dec16 Dec17 Dec18 Dec19 Dec20 Dec21 Dec22 Dec23 Dec24 Dec25
E10
Get a 7-Day Free Trial Premium Member Only Premium Member Only 0.42 0.48 0.35 0.45 0.41

Delta Air Lines Quarterly Data
Sep21 Dec21 Mar22 Jun22 Sep22 Dec22 Mar23 Jun23 Sep23 Dec23 Mar24 Jun24 Sep24 Dec24 Mar25 Jun25 Sep25 Dec25 Mar26 Jun26
E10 Get a 7-Day Free Trial Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only 0.41 0.41 0.41 0.40 0.40

STU:OYC vs UAL, LUV, AAL: E10 Comparison

For the Airlines subindustry, Delta Air Lines's Shiller PE Ratio, along with its competitors' market caps and Shiller PE Ratio data, can be viewed below:

* Competitive companies are chosen from companies within the same industry, with headquarter located in same country, with closest market capitalization; x-axis shows the market cap, and y-axis shows the term value; the bigger the dot, the larger the market cap. Note that "N/A" values will not show up in the chart.


Delta Air Lines Shiller PE Ratio vs Transportation Industry

For the Transportation industry and Industrials sector, Delta Air Lines's Shiller PE Ratio distribution charts can be found below:

* The bar in red indicates where Delta Air Lines's Shiller PE Ratio falls into.


STU:OYC
84GF Score
Delta Air Lines Inc STU:OYC
E10 is just one metric. See GF Score™, valuation, warning signs, and more.
View Full Analysis

Delta Air Lines E10 Calculation

E10 is a concept invented by Prof. Robert Shiller, who uses E10 for his Shiller P/E calculation. When we calculate the today's Shiller P/E ratio of a stock, we use today's price divided by E10.

What is E10? How do we calculate E10?

E10 is the average of the inflation adjusted earnings of a company over the past 10 years. Let's use an example to explain.

If we want to calculate the E10 of Wal-Mart (WMT) for Dec. 31, 2010, we need to have the inflation data and the earnings from 2001 through 2010.

We adjusted the earnings of 2001 earnings data with the total inflation from 2001 through 2010 to the equivalent earnings in 2010. If the total inflation from 2001 to 2010 is 40%, and Wal-Mart earned $1 a share in 2001, then the 2001's equivalent earnings in 2010 is $1.4 a share. If Wal-Mart earns $1 again in 2002, and the total inflation from 2002 through 2010 is 35%, then the equivalent 2002 earnings in 2010 is $1.35. So on and so forth, you get the equivalent earnings of past 10 years. Then you add them together and divided the sum by 10 to get E10.

Please note that we use the CPI data of the country/region where the company is headquartered. If the CPI data for that country/region is not available, then we will use the CPI data of the United States as default.

For example, Delta Air Lines's adjusted earnings per share data for the three months ended in Jun. 2026 was:

Adj_EPS= Earnings per Share (Diluted) /CPI of Jun. 2026 (Change)*Current CPI (Jun. 2026)
=0.353/333.9520*333.9520
=0.353

Current CPI (Jun. 2026) = 333.9520.

Delta Air Lines Quarterly Data

per share eps CPI Adj_EPS
201609 0.251 241.428 0.347
201612 0.133 241.432 0.184
201703 0.120 243.801 0.164
201706 0.240 244.955 0.327
201709 0.225 246.819 0.304
201712 0.059 246.524 0.080
201803 0.107 249.554 0.143
201806 0.213 251.989 0.282
201809 0.274 252.439 0.362
201812 0.218 251.233 0.290
201903 0.161 254.202 0.212
201906 0.326 256.143 0.425
201909 0.350 256.759 0.455
201912 0.257 256.974 0.334
202003 -0.127 258.115 -0.164
202006 -1.333 257.797 -1.727
202009 -1.199 260.280 -1.538
202012 -0.163 260.474 -0.209
202103 -0.259 264.877 -0.327
202106 0.141 271.696 0.173
202109 0.268 274.310 0.326
202112 -0.094 278.802 -0.113
202203 -0.224 287.504 -0.260
202206 0.181 296.311 0.204
202209 0.182 296.808 0.205
202212 0.203 296.797 0.228
202303 -0.089 301.836 -0.098
202306 0.437 305.109 0.478
202309 0.269 307.789 0.292
202312 0.483 306.746 0.526
202403 0.009 312.332 0.010
202406 0.311 314.175 0.331
202409 0.296 315.301 0.314
202412 0.205 315.605 0.217
202503 0.057 319.799 0.060
202506 0.473 322.561 0.490
202509 0.308 324.800 0.317
202512 0.265 324.054 0.273
202603 -0.063 330.213 -0.064
202606 0.353 333.952 0.353

Add all the adjusted EPS together and divide 10 will get our e10.

Frequently Asked Questions Learn more about E10 →
What does a E10 of €0.40 mean?
Delta Air Lines (STU:OYC) has a E10 of €0.40 as of Jun. 2026. E10 represents the company's inflation-adjusted earnings per share over a 10-year period. View historical data on Delta Air Lines and its competitors.
Is Delta Air Lines' E10 too high?
Delta Air Lines' current E10 is €0.40. Overall, Delta Air Lines has a GF Score™ of 84/100 and is considered Significantly Overvalued, reflecting its overall financial health beyond just this single metric.
How does Delta Air Lines' E10 compare to UAL and LUV?
Delta Air Lines' E10 of €0.40 can be compared against companies in the Transportation industry. See the competitive comparison table and distribution chart on this page for a detailed peer-by-peer breakdown.
What is a good E10 for a Transportation company?
A good E10 depends on the Transportation industry context. However, E10 should not be evaluated in isolation — investors should consider it alongside profitability, growth, and financial strength metrics. Use the industry distribution chart on this page to see where any company falls relative to its peers.
What does a high E10 mean?
A high E10 can signal that a stock is expensive relative to its fundamentals. E10 represents the company's inflation-adjusted earnings per share over a 10-year period. View historical data on Delta Air Lines and its competitors. Delta Air Lines's current E10 is €0.40. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is Delta Air Lines stock overvalued right now?
Based on GuruFocus' analysis, Delta Air Lines (STU:OYC) is currently considered Significantly Overvalued. The stock's GF Value™ is €50.39, compared to a current price of €70.43 — trading 39.8% above its estimated fair value. The current E10 is €0.40. Delta Air Lines' overall GF Score™ is 84/100 with 5 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is E10 calculated?
E10 is calculated from a company's financial statements. For Delta Air Lines (STU:OYC), the current E10 is €0.40 as of Jun. 2026. GuruFocus calculates this using data sourced from SEC filings and annual reports. See the calculation section and 30-year financial data on this page for the full breakdown.

Is Delta Air Lines (STU:OYC) Overvalued in 2026?

Based on GuruFocus' analysis, Delta Air Lines stock appears to be overvalued. The current stock price of €70.43 is trading 39.8% above its estimated GF Value™ of €50.39. GuruFocus considers Delta Air Lines to be Significantly Overvalued.

Key valuation signals for STU:OYC:

  • E10: €0.40
  • GF Value™: €50.39 vs. price of €70.43 (39.8% above fair value)
  • GF Score™: 84/100 with 5 warning signs

No single metric tells the full story. See the STU:OYC stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.


Delta Air Lines Business Description

Address Post Office Box 20706, Atlanta, GA, USA, 30320-6001
Atlanta-based Delta Air Lines is one of the world's largest airlines, with a network of over 300 destinations in more than 50 countries. Delta operates a hub-and-spoke network, where it gathers and distributes passengers across the globe through its biggest hubs in Atlanta, New York, Salt Lake City, Detroit, Seattle, and Minneapolis-St. Paul. Delta has historically earned most of its international revenue and profits from flying passengers over the Atlantic Ocean.
84GF Score

Get the complete analysis for STU:OYC

E10 is just one metric. See GF Value™, 30-year financials, guru trades, warning signs, and more.

€70.43
Price
€50.39
GF Value