Lumen Technologies (STU:CYTH) E10: €-1.72 (As of Mar. 2026)

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Director of Data and Quant Analytics at GuruFocus
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STU:CYTH Lumen Technologies Inc STU:CYTH
56 GF Score
Price €5.63
GF Value €3.36
Valuation Significantly Overvalued
! 5 Warning Signs
View Full Analysis

What is Lumen Technologies E10?

Lumen Technologies STU:CYTH -4.09% 56 E10 is €-1.72 as of Mar. 2026. GuruFocus rates STU:CYTH with a GF Score™ of 56/100 and a GF Value™ of €3.36 (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.

Lumen Technologies's adjusted earnings per share data for the three months ended in Mar. 2026 was €-0.173. Add all the adjusted EPS for the past 10 years together and divide 10 will get our e10, which is €-1.72 for the trailing ten years ended in Mar. 2026.

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 Lumen Technologies was 21.40% per year. The lowest was -64.00% per year. And the median was 6.20% per year.

As of today (2026-07-14), Lumen Technologies's current stock price is €5.63. Lumen Technologies's E10 for the quarter that ended in Mar. 2026 was €-1.72. Lumen Technologies's Shiller PE Ratio of today is .

During the past 13 years, the highest Shiller PE Ratio of Lumen Technologies was 301.20. The lowest was 7.17. And the median was 17.92.


Lumen Technologies  (STU:CYTH) 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.

During the past 13 years, the highest Shiller P/E Ratio of Lumen Technologies was 301.20. The lowest was 7.17. And the median was 17.92.


Be Aware

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


Lumen Technologies E10 Related Terms


Lumen Technologies E10 Historical Data

* Premium members only.

The historical data trend for Lumen Technologies'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.

Lumen Technologies E10 Chart

Lumen Technologies 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 0.12 -0.17 -1.06 -1.36 0.00

Lumen Technologies Quarterly Data
Jun21 Sep21 Dec21 Mar22 Jun22 Sep22 Dec22 Mar23 Jun23 Sep23 Dec23 Mar24 Jun24 Sep24 Dec24 Mar25 Jun25 Sep25 Dec25 Mar26
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 -1.37 -1.37 -1.41 0.00 -1.72

STU:CYTH vs GSAT, IRDM, LBRDA: E10 Comparison

For the Telecom Services subindustry, Lumen Technologies'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.


Lumen Technologies Shiller PE Ratio vs Telecommunication Services Industry

For the Telecommunication Services industry and Communication Services sector, Lumen Technologies's Shiller PE Ratio distribution charts can be found below:

* The bar in red indicates where Lumen Technologies's Shiller PE Ratio falls into.


STU:CYTH
56GF Score
Lumen Technologies Inc STU:CYTH
E10 is just one metric. See GF Score™, valuation, warning signs, and more.
View Full Analysis

Lumen Technologies 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, Lumen Technologies's adjusted earnings per share data for the three months ended in Mar. 2026 was:

Adj_EPS= Earnings per Share (Diluted) /CPI of Mar. 2026 (Change)*Current CPI (Mar. 2026)
=-0.173/330.2130*330.2130
=-0.173

Current CPI (Mar. 2026) = 330.2130.

Lumen Technologies Quarterly Data

per share eps CPI Adj_EPS
201606 0.320 241.018 0.438
201609 0.249 241.428 0.341
201612 0.076 241.432 0.104
201703 0.280 243.801 0.379
201706 0.027 244.955 0.036
201709 0.143 246.819 0.191
201712 1.065 246.524 1.427
201803 0.089 249.554 0.118
201806 0.231 251.989 0.303
201809 0.214 252.439 0.280
201812 -1.987 251.233 -2.612
201903 -5.106 254.202 -6.633
201906 0.310 256.143 0.400
201909 0.254 256.759 0.327
201912 0.189 256.974 0.243
202003 0.262 258.115 0.335
202006 0.311 257.797 0.398
202009 0.289 260.280 0.367
202012 -1.743 260.474 -2.210
202103 0.370 264.877 0.461
202106 0.382 271.696 0.464
202109 0.434 274.310 0.522
202112 0.443 278.802 0.525
202203 0.536 287.504 0.616
202206 0.322 296.311 0.359
202209 0.576 296.808 0.641
202212 -2.908 296.797 -3.235
202303 0.486 301.836 0.532
202306 -8.196 305.109 -8.870
202309 -0.075 307.789 -0.080
202312 -1.862 306.746 -2.004
202403 0.055 312.332 0.058
202406 -0.046 314.175 -0.048
202409 -0.135 315.301 -0.141
202412 0.086 315.605 0.090
202503 -0.185 319.799 -0.191
202506 -0.798 322.561 -0.817
202509 -0.528 324.800 -0.537
202512 0.000 324.054 0.000
202603 -0.173 330.213 -0.173

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 €-1.72 mean?
Lumen Technologies (STU:CYTH) has a E10 of €-1.72 as of Mar. 2026. E10 represents the company's inflation-adjusted earnings per share over a 10-year period. View historical data on Lumen Technologies and its competitors.
Is Lumen Technologies' E10 too high?
Lumen Technologies' current E10 is €-1.72. Overall, Lumen Technologies has a GF Score™ of 56/100 and is considered Significantly Overvalued, reflecting its overall financial health beyond just this single metric.
How does Lumen Technologies' E10 compare to GSAT and IRDM?
Lumen Technologies' E10 of €-1.72 can be compared against companies in the Telecommunication Services 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 Telecommunication Services company?
A good E10 depends on the Telecommunication Services 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 Lumen Technologies and its competitors. Lumen Technologies's current E10 is €-1.72. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is Lumen Technologies stock overvalued right now?
Based on GuruFocus' analysis, Lumen Technologies (STU:CYTH) is currently considered Significantly Overvalued. The stock's GF Value™ is €3.36, compared to a current price of €5.63 — trading 67.6% above its estimated fair value. The current E10 is €-1.72. Lumen Technologies' overall GF Score™ is 56/100 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 Lumen Technologies (STU:CYTH), the current E10 is €-1.72 as of Mar. 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 Lumen Technologies (STU:CYTH) Overvalued in 2026?

Based on GuruFocus' analysis, Lumen Technologies stock appears to be overvalued. The current stock price of €5.63 is trading 67.6% above its estimated GF Value™ of €3.36. GuruFocus considers Lumen Technologies to be Significantly Overvalued.

Key valuation signals for STU:CYTH:

  • E10: €-1.72
  • GF Value™: €3.36 vs. price of €5.63 (67.6% above fair value)
  • GF Score™: 56/100 with 5 warning signs

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


Lumen Technologies Business Description

Address 100 CenturyLink Drive, Monroe, LA, USA, 71203
Lumen Technologies is one of the largest telecommunications carriers serving global enterprises. The merger with Level 3 in 2017, the 2022 divestiture of much of its local phone business in rural areas, and the 2026 sale of its remaining consumer fiber network to AT&T have shifted the company's operations away from the legacy consumer business and toward enterprise services, which account for about 85%-90% of revenue. Lumen offers businesses a full suite of communications services, providing colocation and data center services, data transportation, phone service, and internet access.
56GF Score

Get the complete analysis for STU:CYTH

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

€5.63
Price
€3.36
GF Value