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Delta Air LinesMIL:1DAL +9.09%59 Shiller PE Ratio is 28.40 as of Sep. 09, 2026, which is 84% above its 10-year median of 15.41. GuruFocus rates MIL:1DAL with a GF Score™ of 59/100 and a GF Value™ of €51.19 (Significantly Overvalued). The stock has 4 warning signs investors should review. Among 594 Transportation companies, Delta Air Lines ranks worse than 74.75% on this metric.
As of today (2026-09-09), Delta Air Lines's current share price is €68.74. Delta Air Lines's E10 for the quarter that ended in Jun. 2026 was €2.42. Delta Air Lines's Shiller PE Ratio for today is 28.40.
The historical rank and industry rank for Delta Air Lines's Shiller PE Ratio or its related term are showing as below:
MIL:1DAL'
s Shiller PE Ratio Range Over the Past 10 Years
Min: 4.05 Med: 15.41 Max: 66.02
Current: 28.71
During the past years, Delta Air Lines's highest Shiller PE Ratio was 66.02. The lowest was 4.05. And the median was 15.41.
MIL:1DAL's Shiller PE Ratio is ranked worse than 74.75% of 594
companies
in the Transportation industry
Industry Median: 18.385
vs MIL:1DAL: 28.71
E10 is a concept invented by Prof. Robert Shiller, who uses E10 for his Shiller PE Ratio 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 €2.118. Add all the adjusted EPS for the past 10 years together and divide 10 will get our E10, which is €2.42 for the trailing ten years ended in Jun. 2026.
Shiller PE for Stocks: The True Measure of Stock Valuation
Delta Air Lines (MIL:1DAL) Shiller PE Ratio Explanation
Compared with the regular PE Ratio, which works poorly for cyclical businesses, the Shiller PE Ratio smoothed out the fluctuations of profit margins during business cycles. Therefore it is more accurate in reflecting the valuation of the company.
If a company has consistent business performance, the Shiller PE Ratio should give similar results to regular PE Ratio.
Compared with the PS Ratio, the Shiller PE Ratio makes the comparison between different industries more meaningful.
Be Aware
Shiller PE Ratio assumes that over the long term, businesses and profitability revert to their means. If a company's business model does not work in the future compared with the past, Shiller PE Ratio and PS Ratio will give false valuations.
Delta Air Lines Shiller PE Ratio Related Terms
Delta Air Lines Shiller PE Ratio Historical Data
* Premium members only.
The historical data trend for Delta Air Lines's Shiller PE Ratio 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.
MIL:1DAL vs UAL, LUV, AAL: Shiller PE Ratio 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.
For Shiller PE Ratio, 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 PE Ratio is also called PE10.
The Shiller PE Ratio 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 PE Ratio for today is calculated as
* 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's E10 for the quarter that ended in Jun. 2026 is calculated as:
For example, Delta Air Lines's adjusted earnings per share data for the three months ended in Jun. 2026 was:
Add all the adjusted EPS together and divide 10 will get our 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.
Delta Air Lines (MIL:1DAL) has a Shiller PE Ratio of 28.40 as of Sep. 09, 2026. Shiller price-earnings ratio is the ratio of share price to a company's inflation-adjusted earnings over a 10-year period. View historical data on Delta Air Lines and its competitors. This is 84% above median its historical median of 15.41. Over the past decade, Delta Air Lines' Shiller PE Ratio has ranged from 4.05 to 66.02. According to the industry distribution chart, Delta Air Lines ranks #444 out of 594 companies in the Transportation industry, placing it in the top 74.7%.
Is Delta Air Lines' Shiller PE Ratio too high?
Delta Air Lines' current Shiller PE Ratio of 28.40 is 84% above median its 10-year median of 15.41. Over the past 10 years, this metric has ranged from a low of 4.05 to a high of 66.02. The Transportation industry median Shiller PE Ratio is 18.39. Delta Air Lines' value of 28.40 is 54.5% above this industry median. Based on the distribution chart, Delta Air Lines ranks #444 out of 594 companies in the Transportation industry, which is below the industry midpoint. Overall, Delta Air Lines has a GF Score™ of 59/100 and is considered Significantly Overvalued, reflecting its overall financial health beyond just this single metric.
How does Delta Air Lines' Shiller PE Ratio compare to UAL and LUV?
According to the Transportation industry distribution chart, Delta Air Lines ranks #444 out of 594 companies for Shiller PE Ratio. This places Delta Air Lines in the lower half of its industry. The industry median Shiller PE Ratio is 18.39. Delta Air Lines' value of 28.40 is 54.5% above this benchmark. Historically, Delta Air Lines' own Shiller PE Ratio has ranged from 4.05 to 66.02 over the past decade. While the company's 10-year median is 15.41 vs. the industry median of 18.39, Delta Air Lines has consistently been above the industry average. See the competitive comparison table and distribution chart on this page for a detailed peer-by-peer breakdown.
What is a good Shiller PE Ratio for a Transportation company?
The median Shiller PE Ratio among Transportation companies is 18.39, based on 594 companies in the industry. Companies in the top quartile (top 25%) have a Shiller PE Ratio significantly above this median, while those in the bottom quartile fall well below. However, Shiller PE Ratio should not be evaluated in isolation — investors should consider it alongside profitability, growth, and financial strength metrics. Delta Air Lines's current Shiller PE Ratio of 28.40 is 54.5% above the industry median. Use the industry distribution chart on this page to see where any company falls relative to its peers.
What does a high Shiller PE Ratio mean?
A high Shiller PE Ratio can signal that a stock is expensive relative to its fundamentals. Shiller price-earnings ratio is the ratio of share price to a company's inflation-adjusted earnings over a 10-year period. View historical data on Delta Air Lines and its competitors. For the Transportation industry, the median Shiller PE Ratio is 18.39 — values significantly above this may indicate overvaluation, while values below may suggest a bargain or underlying issues. Delta Air Lines's current Shiller PE Ratio is 28.40, which is 84% above median its own 10-year median of 15.41. 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 (MIL:1DAL) is currently considered Significantly Overvalued. The stock's GF Value™ is €51.19, compared to a current price of €68.74 — trading 34.3% above its estimated fair value. The current Shiller PE Ratio is 28.40, which is 84% above median its 10-year median of 15.41 and 54.5% above the Transportation industry median of 18.39. Delta Air Lines' overall GF Score™ is 59/100 with 4 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is Shiller PE Ratio calculated?
Shiller PE Ratio is calculated from a company's financial statements. For Delta Air Lines (MIL:1DAL), the current Shiller PE Ratio is 28.40 as of Sep. 09, 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 (MIL:1DAL) Overvalued in 2026?
Based on GuruFocus' analysis, Delta Air Lines stock appears to be overvalued.
The current stock price of €68.74 is trading 34.3% above its estimated GF Value™ of €51.19.
GuruFocus considers Delta Air Lines to be Significantly Overvalued.
Key valuation signals for MIL:1DAL:
Shiller PE Ratio: 28.40 (84% above median its 10-year median of 15.41)
GF Value™: €51.19 vs. price of €68.74 (34.3% above fair value)
Industry Position: 54.5% above the Transportation median (#444 of 594)
No single metric tells the full story. See the MIL:1DAL stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.
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.
59GF Score
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