GCS Holdings (ROCO:4991) E10: NT$0.00 (As of Mar. 2026)

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Director of Data and Quant Analytics at GuruFocus
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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.

ROCO:4991 GCS Holdings Inc ROCO:4991
62 GF Score
Price NT$382.50
GF Value NT$111.20
Valuation Significantly Overvalued
! 1 Warning Sign
View Full Analysis

What is GCS Holdings E10?

GCS Holdings ROCO:4991 +9.91% 62 E10 is NT$0.00 as of Mar. 2026. GuruFocus rates ROCO:4991 with a GF Score™ of 62/100 and a GF Value™ of NT$111.20 (Significantly Overvalued). The stock has 1 warning sign 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.

GCS Holdings's adjusted earnings per share data for the three months ended in Mar. 2026 was NT$1.650. Add all the adjusted EPS for the past 10 years together and divide 10 will get our e10, which is NT$0.00 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.

As of today (2026-07-22), GCS Holdings's current stock price is NT$382.50. GCS Holdings's E10 for the quarter that ended in Mar. 2026 was NT$0.00. GCS Holdings's Shiller PE Ratio of today is .

During the past 13 years, the highest Shiller PE Ratio of GCS Holdings was 1625.39. The lowest was 16.70. And the median was 29.93.


GCS Holdings  (ROCO:4991) 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 GCS Holdings was 1625.39. The lowest was 16.70. And the median was 29.93.


Be Aware

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


GCS Holdings E10 Related Terms


GCS Holdings E10 Historical Data

* Premium members only.

The historical data trend for GCS Holdings'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.

GCS Holdings E10 Chart

GCS Holdings 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 2.17 1.24 0.29 -0.27 -0.71

GCS Holdings 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 -0.41 -0.50 -0.61 -0.71 0.00

ROCO:4991 vs AMAT, LRCX, KLAC: E10 Comparison

For the Semiconductor Equipment & Materials subindustry, GCS Holdings'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.


GCS Holdings Shiller PE Ratio vs Semiconductors Industry

For the Semiconductors industry and Technology sector, GCS Holdings's Shiller PE Ratio distribution charts can be found below:

* The bar in red indicates where GCS Holdings's Shiller PE Ratio falls into.


ROCO:4991
62GF Score
GCS Holdings Inc ROCO:4991
E10 is just one metric. See GF Score™, valuation, warning signs, and more.
View Full Analysis

GCS Holdings 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, GCS Holdings'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)
=1.65/330.2130*330.2130
=1.650

Current CPI (Mar. 2026) = 330.2130.

GCS Holdings Quarterly Data

per share eps CPI Adj_EPS
201606 0.908 241.018 1.244
201609 1.194 241.428 1.633
201612 0.612 241.432 0.837
201703 0.819 243.801 1.109
201706 0.888 244.955 1.197
201709 1.451 246.819 1.941
201712 0.997 246.524 1.335
201803 1.036 249.554 1.371
201806 1.135 251.989 1.487
201809 1.125 252.439 1.472
201812 0.632 251.233 0.831
201903 0.168 254.202 0.218
201906 0.977 256.143 1.260
201909 0.671 256.759 0.863
201912 1.145 256.974 1.471
202003 0.030 258.115 0.038
202006 0.069 257.797 0.088
202009 -0.385 260.280 -0.488
202012 -0.977 260.474 -1.239
202103 -0.977 264.877 -1.218
202106 -0.494 271.696 -0.600
202109 -0.938 274.310 -1.129
202112 -1.727 278.802 -2.045
202203 -1.530 287.504 -1.757
202206 -1.372 296.311 -1.529
202209 -2.004 296.808 -2.230
202212 -3.514 296.797 -3.910
202303 -2.626 301.836 -2.873
202306 -2.379 305.109 -2.575
202309 -2.043 307.789 -2.192
202312 -0.030 306.746 -0.032
202403 -1.875 312.332 -1.982
202406 -1.165 314.175 -1.224
202409 1.352 315.301 1.416
202412 -0.452 315.605 -0.473
202503 -0.700 319.799 -0.723
202506 0.118 322.561 0.121
202509 0.128 324.800 0.130
202512 0.594 324.054 0.605
202603 1.650 330.213 1.650

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 NT$0.00 mean?
GCS Holdings (ROCO:4991) has a E10 of NT$0.00 as of Mar. 2026. E10 represents the company's inflation-adjusted earnings per share over a 10-year period. View historical data on GCS Holdings and its competitors.
Is GCS Holdings' E10 too high?
GCS Holdings' current E10 is NT$0.00. Overall, GCS Holdings has a GF Score™ of 62/100 and is considered Significantly Overvalued, reflecting its overall financial health beyond just this single metric.
How does GCS Holdings' E10 compare to AMAT and LRCX?
GCS Holdings' E10 of NT$0.00 can be compared against companies in the Semiconductors 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 Semiconductors company?
A good E10 depends on the Semiconductors 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 GCS Holdings and its competitors. GCS Holdings's current E10 is NT$0.00. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is GCS Holdings stock overvalued right now?
Based on GuruFocus' analysis, GCS Holdings (ROCO:4991) is currently considered Significantly Overvalued. The stock's GF Value™ is NT$111.20, compared to a current price of NT$382.50 — trading 244% above its estimated fair value. The current E10 is NT$0.00. GCS Holdings' overall GF Score™ is 62/100 with 1 warning sign 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 GCS Holdings (ROCO:4991), the current E10 is NT$0.00 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 GCS Holdings (ROCO:4991) Overvalued in 2026?

Based on GuruFocus' analysis, GCS Holdings stock appears to be overvalued. The current stock price of NT$382.50 is trading 244% above its estimated GF Value™ of NT$111.20. GuruFocus considers GCS Holdings to be Significantly Overvalued.

Key valuation signals for ROCO:4991:

  • E10: NT$0.00
  • GF Value™: NT$111.20 vs. price of NT$382.50 (244% above fair value)
  • GF Score™: 62/100 with 1 warning sign

No single metric tells the full story. See the ROCO:4991 stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.


GCS Holdings Business Description

Address 23155 Kashiwa Court, Torrance, CA, USA, 90505
GCS Holdings Inc through its subsidiaries, is engaged in the manufacturing of compound semiconductor wafers and foundry-related services as well as the licensing of intellectual property. It is also engaged in the research, development, manufacture, and sales of optoelectronics technology products. Its portfolio offerings include Radio Frequency Integrated Circuits (RFIC) and millimeter-wave integrated circuits for the wireless markets, power devices for power electronics, and Photodetectors and Lasers for the optical communications market. Geographically, the company generates a majority of its revenue from China and the rest from the United States, Taiwan, and other markets.
62GF Score

Get the complete analysis for ROCO:4991

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

NT$382.50
Price
NT$111.20
GF Value