Delta Air Lines (BSP:DEAI34) Cyclically Adjusted Book per Share: R$102.90 (As of Jun. 2026)

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Director of Data and Quant Analytics at GuruFocus
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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.

BSP:DEAI34 Delta Air Lines Inc BSP:DEAI34
75 GF Score
Price R$446.00
GF Value R$299.92
Valuation Significantly Overvalued
! 6 Warning Signs
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What is Delta Air Lines Cyclically Adjusted Book per Share?

Delta Air Lines BSP:DEAI34 75 Cyclically Adjusted Book per Share is R$102.90 as of Jun. 2026. GuruFocus rates BSP:DEAI34 with a GF Score™ of 75/100 and a GF Value™ of R$299.92 (Significantly Overvalued). The stock has 6 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 R$169.979. 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 R$102.90 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 -100.00% 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 (2026-07-14), Delta Air Lines's current stock price is R$446.00. Delta Air Lines's Cyclically Adjusted Book per Share for the quarter that ended in Jun. 2026 was R$102.90. Delta Air Lines's Cyclically Adjusted PB Ratio of today is 4.33.

During the past 13 years, the highest Cyclically Adjusted PB Ratio of Delta Air Lines was 22.92. The lowest was 1.67. And the median was 3.46.


Delta Air Lines  (BSP:DEAI34) 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
=446.00/102.90
=4.33

* 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 22.92. The lowest was 1.67. And the median was 3.46.


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 73.10 79.47 79.98 106.24 105.68

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 96.58 96.79 105.68 103.39 102.90

BSP:DEAI34 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.


BSP:DEAI34
75GF Score
Delta Air Lines Inc BSP:DEAI34
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)
=169.979/335.1230*335.1230
=169.979

Current CPI (Jun. 2026) = 335.1230.

Delta Air Lines Quarterly Data

Book Value per Share CPI Adj_Book
201609 55.267 241.428 76.715
201612 56.396 241.432 78.281
201703 55.043 243.801 75.661
201706 61.349 244.955 83.932
201709 61.514 246.819 83.522
201712 58.380 246.524 79.361
201803 58.613 249.554 78.711
201806 70.126 251.989 93.261
201809 82.124 252.439 109.023
201812 78.171 251.233 104.273
201903 75.706 254.202 99.806
201906 82.771 256.143 108.293
201909 95.977 256.759 125.270
201912 98.070 256.974 127.894
202003 109.615 258.115 142.318
202006 70.685 257.797 91.887
202009 28.425 260.280 36.599
202012 12.366 260.474 15.910
202103 4.246 264.877 5.372
202106 10.066 271.696 12.416
202109 21.495 274.310 26.260
202112 34.346 278.802 41.284
202203 23.218 287.504 27.064
202206 30.001 296.311 33.931
202209 37.537 296.808 42.383
202212 53.839 296.797 60.791
202303 50.731 301.836 56.326
202306 61.103 305.109 67.114
202309 70.811 307.789 77.100
202312 84.564 306.746 92.387
202403 86.051 312.332 92.330
202406 103.363 314.175 110.255
202409 117.110 315.301 124.472
202412 144.326 315.605 153.252
202503 136.220 319.799 142.747
202506 148.126 322.561 153.895
202509 154.591 324.800 159.504
202512 174.178 324.054 180.128
202603 162.191 330.213 164.603
202606 169.979 335.123 169.979

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 R$102.90 mean?
Delta Air Lines (BSP:DEAI34) has a Cyclically Adjusted Book per Share of R$102.90 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 R$102.90. Overall, Delta Air Lines has a GF Score™ of 75/100 and is considered Significantly Overvalued, 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 R$102.90 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 R$102.90. 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 (BSP:DEAI34) is currently considered Significantly Overvalued. The stock's GF Value™ is R$299.92, compared to a current price of R$446.00 — trading 48.7% above its estimated fair value. The current Cyclically Adjusted Book per Share is R$102.90. Delta Air Lines' overall GF Score™ is 75/100 with 6 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 (BSP:DEAI34), the current Cyclically Adjusted Book per Share is R$102.90 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 (BSP:DEAI34) Overvalued in 2026?

Based on GuruFocus' analysis, Delta Air Lines stock appears to be overvalued. The current stock price of R$446.00 is trading 48.7% above its estimated GF Value™ of R$299.92. GuruFocus considers Delta Air Lines to be Significantly Overvalued.

Key valuation signals for BSP:DEAI34:

  • Cyclically Adjusted Book per Share: R$102.90
  • GF Value™: R$299.92 vs. price of R$446.00 (48.7% above fair value)
  • GF Score™: 75/100 with 6 warning signs

No single metric tells the full story. See the BSP:DEAI34 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.
75GF Score

Get the complete analysis for BSP:DEAI34

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

R$446.00
Price
R$299.92
GF Value