Formosa Optical Technology Co (ROCO:5312) Cyclically Adjusted Book per Share: NT$51.80 (As of Dec. 2025)

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ROCO:5312 Formosa Optical Technology Co Ltd ROCO:5312
81 GF Score
Price NT$89.80
GF Value NT$108.89
Valuation Modestly Undervalued
! 4 Warning Signs
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What is Formosa Optical Technology Co Cyclically Adjusted Book per Share?

Formosa Optical Technology Co ROCO:5312 +1.01% 81 Cyclically Adjusted Book per Share is NT$51.80 as of Dec. 2025. GuruFocus rates ROCO:5312 with a GF Score™ of 81/100 and a GF Value™ of NT$108.89 (Modestly Undervalued). The stock has 4 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.

Formosa Optical Technology Co's adjusted book value per share for the three months ended in Dec. 2025 was NT$62.083. 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 NT$51.80 for the trailing ten years ended in Dec. 2025.

During the past 12 months, Formosa Optical Technology Co's average Cyclically Adjusted Book Growth Rate was 4.20% per year. During the past 3 years, the average Cyclically Adjusted Book Growth Rate was 4.80% per year. During the past 5 years, the average Cyclically Adjusted Book Growth Rate was 7.10% 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 Formosa Optical Technology Co was 9.20% per year. The lowest was 4.80% per year. And the median was 7.75% per year.

As of today (2026-07-16), Formosa Optical Technology Co's current stock price is NT$89.80. Formosa Optical Technology Co's Cyclically Adjusted Book per Share for the quarter that ended in Dec. 2025 was NT$51.80. Formosa Optical Technology Co's Cyclically Adjusted PB Ratio of today is 1.73.

During the past 13 years, the highest Cyclically Adjusted PB Ratio of Formosa Optical Technology Co was 3.31. The lowest was 1.26. And the median was 1.78.


Formosa Optical Technology Co  (ROCO:5312) 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.

Formosa Optical Technology Co's Cyclically Adjusted PB Ratio of today is calculated as

Cyclically Adjusted PB Ratio=Share Price/Cyclically Adjusted Book per Share
=89.80/51.80
=1.73

* 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 Formosa Optical Technology Co was 3.31. The lowest was 1.26. And the median was 1.78.


Be Aware

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


Formosa Optical Technology Co Cyclically Adjusted Book per Share Related Terms


Formosa Optical Technology Co Cyclically Adjusted Book per Share Historical Data

* Premium members only.

The historical data trend for Formosa Optical Technology Co'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.

Formosa Optical Technology Co Cyclically Adjusted Book per Share Chart

Formosa Optical Technology Co 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 41.01 45.03 47.34 49.69 51.80

Formosa Optical Technology Co Quarterly Data
Mar21 Jun21 Sep21 Dec21 Mar22 Jun22 Sep22 Dec22 Mar23 Jun23 Sep23 Dec23 Mar24 Jun24 Sep24 Dec24 Mar25 Jun25 Sep25 Dec25
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 49.69 50.59 51.13 51.66 51.80

ROCO:5312 vs ISRG, BDX, MDLN: Cyclically Adjusted Book per Share Comparison

For the Medical Instruments & Supplies subindustry, Formosa Optical Technology Co'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.


Formosa Optical Technology Co Cyclically Adjusted PB Ratio vs Medical Devices & Instruments Industry

For the Medical Devices & Instruments industry and Healthcare sector, Formosa Optical Technology Co's Cyclically Adjusted PB Ratio distribution charts can be found below:

* The bar in red indicates where Formosa Optical Technology Co's Cyclically Adjusted PB Ratio falls into.


ROCO:5312
81GF Score
Formosa Optical Technology Co Ltd ROCO:5312
Cyclically Adjusted Book per Share is just one metric. See GF Score™, valuation, warning signs, and more.
View Full Analysis

Formosa Optical Technology Co 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, Formosa Optical Technology Co's adjusted Book Value per Share data for the three months ended in Dec. 2025 was:

Adj_Book= Book Value per Share /CPI of Dec. 2025 (Change)*Current CPI (Dec. 2025)
=62.083/324.0540*324.0540
=62.083

Current CPI (Dec. 2025) = 324.0540.

Formosa Optical Technology Co Quarterly Data

Book Value per Share CPI Adj_Book
201603 39.234 238.132 53.390
201606 36.413 241.018 48.958
201609 37.190 241.428 49.918
201612 38.040 241.432 51.058
201703 38.460 243.801 51.120
201706 35.964 244.955 47.577
201709 37.467 246.819 49.191
201712 38.461 246.524 50.557
201803 40.089 249.554 52.057
201806 37.378 251.989 48.068
201809 37.519 252.439 48.163
201812 39.516 251.233 50.970
201903 41.803 254.202 53.290
201906 39.221 256.143 49.620
201909 39.978 256.759 50.456
201912 42.068 256.974 53.049
202003 42.537 258.115 53.404
202006 38.938 257.797 48.946
202009 40.947 260.280 50.980
202012 43.301 260.474 53.870
202103 44.452 264.877 54.383
202106 44.542 271.696 53.126
202109 41.420 274.310 48.931
202112 44.078 278.802 51.232
202203 47.142 287.504 53.135
202206 43.227 296.311 47.274
202209 42.295 296.808 46.178
202212 43.172 296.797 47.137
202303 46.867 301.836 50.317
202306 44.491 305.109 47.254
202309 46.660 307.789 49.126
202312 49.246 306.746 52.025
202403 53.231 312.332 55.229
202406 52.755 314.175 54.414
202409 55.154 315.301 56.685
202412 57.824 315.605 59.372
202503 59.945 319.799 60.743
202506 50.673 322.561 50.908
202509 58.005 324.800 57.872
202512 62.083 324.054 62.083

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 NT$51.80 mean?
Formosa Optical Technology Co (ROCO:5312) has a Cyclically Adjusted Book per Share of NT$51.80 as of Dec. 2025. 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 Formosa Optical Technology Co and its competitors.
Is Formosa Optical Technology Co's Cyclically Adjusted Book per Share too high?
Formosa Optical Technology Co's current Cyclically Adjusted Book per Share is NT$51.80. Overall, Formosa Optical Technology Co has a GF Score™ of 81/100 and is considered Modestly Undervalued, reflecting its overall financial health beyond just this single metric.
How does Formosa Optical Technology Co's Cyclically Adjusted Book per Share compare to ISRG and BDX?
Formosa Optical Technology Co's Cyclically Adjusted Book per Share of NT$51.80 can be compared against companies in the Medical Devices & Instruments 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 Medical Devices & Instruments company?
A good Cyclically Adjusted Book per Share depends on the Medical Devices & Instruments 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 Formosa Optical Technology Co and its competitors. Formosa Optical Technology Co's current Cyclically Adjusted Book per Share is NT$51.80. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is Formosa Optical Technology Co stock overvalued right now?
Based on GuruFocus' analysis, Formosa Optical Technology Co (ROCO:5312) is currently considered Modestly Undervalued. The stock's GF Value™ is NT$108.89, compared to a current price of NT$89.80 — trading 17.5% below its estimated fair value. The current Cyclically Adjusted Book per Share is NT$51.80. Formosa Optical Technology Co's overall GF Score™ is 81/100 with 4 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 Formosa Optical Technology Co (ROCO:5312), the current Cyclically Adjusted Book per Share is NT$51.80 as of Dec. 2025. 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 Formosa Optical Technology Co (ROCO:5312) Overvalued in 2026?

Based on GuruFocus' analysis, Formosa Optical Technology Co stock appears to be undervalued. The current stock price of NT$89.80 is trading 17.5% below its estimated GF Value™ of NT$108.89. GuruFocus considers Formosa Optical Technology Co to be Modestly Undervalued.

Key valuation signals for ROCO:5312:

  • Cyclically Adjusted Book per Share: NT$51.80
  • GF Value™: NT$108.89 vs. price of NT$89.80 (17.5% below fair value)
  • GF Score™: 81/100 with 4 warning signs

No single metric tells the full story. See the ROCO:5312 stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.


Formosa Optical Technology Co Business Description

Address No. 97, Xintai 5th Road, 16th Floor, Section 1, Xizhi District, New Taipei City, TWN
Formosa Optical Technology Co Ltd is mainly engaged in the eyewear business, including optometry services and the retail business selling contact lenses and eye drops. The Group mainly derives revenue from the business divisions of Formosa Optical Technology and Bo Wei Optical, with Formosa Optical Technology generating maximum revenue. The majority of revenue is derived from the sale of glasses. The Group generates the majority of its revenue from Taiwan.
81GF Score

Get the complete analysis for ROCO:5312

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

NT$89.80
Price
NT$108.89
GF Value