Delta Air Lines (XBUL:OYC) Cyclically Adjusted Book per Share: лв12.15 (As of Jun. 2026)

Author: Vera Yuan Vera Yuan
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Director of Data and Quant Analytics at GuruFocus
Focused on building reliable datasets, financial models, and research tools for value-minded investors. Committed to turning complex data into practical guidance for value-investing and long-term wealth.
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Founder & CEO of GuruFocus
Dr. Charlie Tian is the founder and CEO of GuruFocus.com, a leading global investment research platform established in 2004. With a Ph.D. in physics, Dr. Tian transitioned from science to finance, applying a data-driven, disciplined approach to value investing.

XBUL:OYC Delta Air Lines Inc XBUL:OYC
81 GF Score
Price лв57.43
GF Value лв37.78
! 7 Warning Signs
View Full Analysis

What is Delta Air Lines Cyclically Adjusted Book per Share?

Delta Air Lines XBUL:OYC 81 Cyclically Adjusted Book per Share is лв12.15 as of Jun. 2026. GuruFocus rates XBUL:OYC with a GF Score™ of 81/100 and a GF Value™ of лв37.78. The stock has 7 warning signs investors should review.

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. The similar calculation is applied by GuruFocus to calculate the Cyclically Adjusted Book per Share and the Cyclically Adjusted PB Ratio. The Cyclically Adjusted Book per Share is the average of the inflation adjusted Book Value per Share of a company over the past 10 years.

Delta Air Lines's adjusted book value per share for the three months ended in Jun. 2026 was лв56.974. Add all the adjusted book value per share for the past 10 years together and divide the count will get our Cyclically Adjusted Book per Share, which is лв12.15 for the trailing ten years ended in Jun. 2026.

During the past 12 months, Delta Air Lines's average Cyclically Adjusted Book Growth Rate was 10.00% per year. During the past 3 years, the average Cyclically Adjusted Book Growth Rate was 7.80% per year. During the past 5 years, the average Cyclically Adjusted Book Growth Rate was 9.20% 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 Cyclically Adjusted Book Growth Rate using Cyclically Adjusted Book per Share data.

During the past 13 years, the highest 3-Year average Cyclically Adjusted Book Growth Rate of Delta Air Lines was 41.80% per year. The lowest was -90.80% per year. And the median was 5.10% per year.

As of today (2026-07-31), Delta Air Lines's current stock price is лв57.43. Delta Air Lines's Cyclically Adjusted Book per Share for the quarter that ended in Jun. 2026 was лв12.15. Delta Air Lines's Cyclically Adjusted PB Ratio of today is 4.73.

During the past 13 years, the highest Cyclically Adjusted PB Ratio of Delta Air Lines was 22.81. The lowest was 1.67. And the median was 3.47.


Delta Air Lines  (XBUL:OYC) Cyclically Adjusted Book per Share Explanation

If a company grows much fast than inflation, Cyclically Adjusted Book per Share may underestimate the company's equity. Cyclically Adjusted PB Ratio can seem to be too high even the actual PB Ratio is low.

For the Cyclically Adjusted PB Ratio, the book value of the past 10 years are inflation-adjusted and averaged. The result is used for P/B calculation. Since it looks at the average over the last 10 years, the Cyclically Adjusted PB Ratio is also called CAPB Ratio.

The Shiller PE Ratio was first used by professor Robert Shiller. He uses E10 for his Shiller PE Ratio calculation. E10 is the average of the inflation adjusted earnings per share of a company over the past 10 years. The similar calculation is applied by GuruFocus to calculate the Cyclically Adjusted PB Ratio. The Cyclically Adjusted Book per Share is the average of the inflation adjusted book value per share of a company over the past 10 years.

Delta Air Lines's Cyclically Adjusted PB Ratio of today is calculated as

Cyclically Adjusted PB Ratio=Share Price/Cyclically Adjusted Book per Share
=57.43/12.15
=4.73

* 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 Cyclically Adjusted PB Ratio of Delta Air Lines was 22.81. The lowest was 1.67. And the median was 3.47.


Be Aware

Cyclically Adjusted PB Ratio works better for cyclical companies. It gives you a better idea on the company's real book value.


Delta Air Lines Cyclically Adjusted Book per Share Related Terms


Delta Air Lines Cyclically Adjusted Book per Share Historical Data

* Premium members only.

The historical data trend for Delta Air Lines's Cyclically Adjusted Book per Share 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 Cyclically Adjusted Book per Share Chart

Delta Air Lines Annual Data
Trend Dec16 Dec17 Dec18 Dec19 Dec20 Dec21 Dec22 Dec23 Dec24 Dec25
Cyclically Adjusted Book per Share
Get a 7-Day Free Trial Premium Member Only Premium Member Only 0.00 0.00 0.00 0.00 15.46

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
Cyclically Adjusted Book per Share 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 0.00 0.00 15.46 16.68 12.15

XBUL:OYC vs UAL, LUV, AAL: Cyclically Adjusted Book per Share Comparison

For the Airlines subindustry, Delta Air Lines's Cyclically Adjusted PB Ratio, along with its competitors' market caps and Cyclically Adjusted PB 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 Cyclically Adjusted PB Ratio vs Transportation Industry

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

* The bar in red indicates where Delta Air Lines's Cyclically Adjusted PB Ratio falls into.


XBUL:OYC
81GF Score
Delta Air Lines Inc XBUL:OYC
Cyclically Adjusted Book per Share is just one metric. See GF Score™, valuation, warning signs, and more.
View Full Analysis

Delta Air Lines Cyclically Adjusted Book per Share Calculation

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. The similar calculation is applied by GuruFocus to calculate the Cyclically Adjusted Book per Share and the Cyclically Adjusted PB Ratio. The Cyclically Adjusted Book per Share is the average of the inflation adjusted Book Value per Share of a company over the past 10 years.

What is Cyclically Adjusted Book per Share? How do we calculate Cyclically Adjusted Book per Share?

Cyclically Adjusted Book per Share is the average of the inflation adjusted Book Value per Share of a company over the past 10 years. Let's use an example to explain.

If we want to calculate the Cyclically Adjusted Book per Share of Wal-Mart (WMT) for Dec. 31, 2010, we need to have the inflation data and the book value per share from 2001 through 2010.

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

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 Book Value per Share data for the three months ended in Jun. 2026 was:

Adj_Book= Book Value per Share /CPI of Jun. 2026 (Change)*Current CPI (Jun. 2026)
=56.974/333.9520*333.9520
=56.974

Current CPI (Jun. 2026) = 333.9520.

Delta Air Lines Quarterly Data

Book Value per Share CPI Adj_Book
201609 29.178 241.428 40.360
201612 28.879 241.432 39.946
201703 30.227 243.801 41.404
201706 31.974 244.955 43.591
201709 33.728 246.819 45.635
201712 30.430 246.524 41.222
201803 30.701 249.554 41.084
201806 31.939 251.989 42.328
201809 34.329 252.439 45.414
201812 34.573 251.233 45.956
201903 33.855 254.202 44.476
201906 36.870 256.143 48.070
201909 40.015 256.759 52.045
201912 41.037 256.974 53.330
202003 38.530 258.115 49.851
202006 23.399 257.797 30.311
202009 9.041 260.280 11.600
202012 4.128 260.474 5.292
202103 1.294 264.877 1.631
202106 3.438 271.696 4.226
202109 6.993 274.310 8.513
202112 10.432 278.802 12.496
202203 8.013 287.504 9.308
202206 10.208 296.311 11.505
202209 12.295 296.808 13.834
202212 17.629 296.797 19.836
202303 16.728 301.836 18.508
202306 21.622 305.109 23.666
202309 24.626 307.789 26.719
202312 29.642 306.746 32.271
202403 29.679 312.332 31.733
202406 32.960 314.175 35.035
202409 36.321 315.301 38.469
202412 40.629 315.605 42.991
202503 40.631 319.799 42.429
202506 45.874 322.561 47.494
202509 49.508 324.800 50.903
202512 54.833 324.054 56.508
202603 53.267 330.213 53.870
202606 56.974 333.952 56.974

Add all the adjusted book value per share together and divide the count will get our Cyclically Adjusted Book per Share.

What does a Cyclically Adjusted Book per Share of лв12.15 mean?
Delta Air Lines (XBUL:OYC) has a Cyclically Adjusted Book per Share of лв12.15 as of Jun. 2026. Cyclically adjusted book value per share represents the company's inflation-adjusted book value per share over a 10-year period. View historical data on Delta Air Lines and its competitors.
Is Delta Air Lines' Cyclically Adjusted Book per Share too high?
Delta Air Lines' current Cyclically Adjusted Book per Share is лв12.15. Overall, Delta Air Lines has a GF Score™ of 81/100, reflecting its overall financial health beyond just this single metric.
How does Delta Air Lines' Cyclically Adjusted Book per Share compare to UAL and LUV?
Delta Air Lines' Cyclically Adjusted Book per Share of лв12.15 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 Cyclically Adjusted Book per Share for a Transportation company?
A good Cyclically Adjusted Book per Share depends on the Transportation industry context. However, Cyclically Adjusted Book per Share 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 Cyclically Adjusted Book per Share mean?
A high Cyclically Adjusted Book per Share can signal that a stock is expensive relative to its fundamentals. Cyclically adjusted book value per share represents the company's inflation-adjusted book value per share over a 10-year period. View historical data on Delta Air Lines and its competitors. Delta Air Lines's current Cyclically Adjusted Book per Share is лв12.15. 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?
Delta Air Lines (XBUL:OYC) has a current Cyclically Adjusted Book per Share of лв12.15. The stock's GF Value™ is лв37.78, compared to a current price of лв57.43 — trading 52% above its estimated fair value. The current Cyclically Adjusted Book per Share is лв12.15. Delta Air Lines' overall GF Score™ is 81/100 with 7 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is Cyclically Adjusted Book per Share calculated?
Cyclically Adjusted Book per Share is calculated from a company's financial statements. For Delta Air Lines (XBUL:OYC), the current Cyclically Adjusted Book per Share is лв12.15 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 (XBUL:OYC) Overvalued in 2026?

Based on GuruFocus' analysis, Delta Air Lines stock appears to be overvalued. The current stock price of лв57.43 is trading 52% above its estimated GF Value™ of лв37.78.

Key valuation signals for XBUL:OYC:

  • Cyclically Adjusted Book per Share: лв12.15
  • GF Value™: лв37.78 vs. price of лв57.43 (52% above fair value)
  • GF Score™: 81/100 with 7 warning signs

No single metric tells the full story. See the XBUL: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.
81GF Score

Get the complete analysis for XBUL:OYC

Cyclically Adjusted Book per Share is just one metric. See GF Value™, 30-year financials, guru trades, warning signs, and more.

лв57.43
Price
лв37.78
GF Value