Idemitsu Kosan CoIDKOF 68 Cyclically Adjusted PB Ratio is 1.11 as of Jul. 11, 2026, which is 29% above its 10-year median of 0.86. GuruFocus rates IDKOF with a GF Score™ of 68/100 and a GF Value™ of $6.74 (Modestly Overvalued). The stock has 4 warning signs investors should review. Among 772 Oil & Gas companies, Idemitsu Kosan Co ranks better than 51.68% on this metric.
The historical rank and industry rank for Idemitsu Kosan Co's Cyclically Adjusted PB Ratio or its related term are showing as below:
IDKOF'
s Cyclically Adjusted PB Ratio Range Over the Past 10 Years
Min: 0.54 Med: 0.86 Max: 1.69
Current: 1.13
During the past years, Idemitsu Kosan Co's highest Cyclically Adjusted PB Ratio was 1.69. The lowest was 0.54. And the median was 0.86.
IDKOF's Cyclically Adjusted PB Ratio is ranked better than 51.68% of 772
companies
in the Oil & Gas industry
Industry Median: 1.18
vs IDKOF: 1.13
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.
Idemitsu Kosan Co's adjusted book value per share data for the three months ended in Mar. 2026 was $9.922. 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 $6.75 for the trailing ten years ended in Mar. 2026.
Shiller PE for Stocks: The True Measure of Stock Valuation
Idemitsu Kosan Co (OTCPK:IDKOF) Cyclically Adjusted PB Ratio Explanation
Compared with the regular PB Ratio, which works poorly for cyclical businesses, the Cyclically Adjusted PB Ratio smoothed out the fluctuations of book value during business cycles. Therefore it is more accurate in reflecting the valuation of the company.
If a company has consistent business performance, the Cyclically Adjusted PB Ratio should give similar results to regular PB Ratio.
Idemitsu Kosan Co Cyclically Adjusted PB Ratio Related Terms
Idemitsu Kosan Co Cyclically Adjusted PB Ratio Historical Data
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The historical data trend for Idemitsu Kosan Co's Cyclically Adjusted PB Ratio 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.
Idemitsu Kosan Co Cyclically Adjusted PB Ratio Chart
IDKOF vs VLO, MPC, PSX: Cyclically Adjusted PB Ratio Comparison
For the Oil & Gas Refining & Marketing subindustry, Idemitsu Kosan 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.
Idemitsu Kosan Co Cyclically Adjusted PB Ratio vs Oil & Gas Industry
For the Oil & Gas industry and Energy sector, Idemitsu Kosan Co's Cyclically Adjusted PB Ratio distribution charts can be found below:
* The bar in red indicates where Idemitsu Kosan Co's Cyclically Adjusted PB Ratio falls into.
Idemitsu Kosan Co Cyclically Adjusted PB Ratio Calculation
Like the Shiller PE Ratio, the Cyclically Adjusted PB Ratio takes the Book Value per Share from the past 10 years, adjusts it for inflation, and then calculates the average. This average is then used for the P/B calculation. Because it considers this 10-year average, it's often referred to as the CAPB Ratio.
The Shiller PE Ratio was first used by professor Robert Shiller to measure the valuation of the overall market. The similar calculation is applied by GuruFocus to calculate the Cyclically Adjusted PB Ratio.
Idemitsu Kosan Co's Cyclically Adjusted PB Ratio for today is calculated as
* 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.
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.
What does a Cyclically Adjusted PB Ratio of 1.11 mean?
Idemitsu Kosan Co (IDKOF) has a Cyclically Adjusted PB Ratio of 1.11 as of Jul. 11, 2026. Cyclically Adjusted PB Ratio is the ratio of share price to a company's inflation-adjusted book value per share over a 10-year period. View historical data on Idemitsu Kosan Co and its competitors. This is 29% above median its historical median of 0.86. Over the past decade, Idemitsu Kosan Co's Cyclically Adjusted PB Ratio has ranged from 0.54 to 1.69. According to the industry distribution chart, Idemitsu Kosan Co ranks #373 out of 772 companies in the Oil & Gas industry, placing it in the top 48.3%.
Is Idemitsu Kosan Co's Cyclically Adjusted PB Ratio too high?
Idemitsu Kosan Co's current Cyclically Adjusted PB Ratio of 1.11 is 29% above median its 10-year median of 0.86. Over the past 10 years, this metric has ranged from a low of 0.54 to a high of 1.69. The Oil & Gas industry median Cyclically Adjusted PB Ratio is 1.18. Idemitsu Kosan Co's value of 1.11 is 5.9% below this industry median. Based on the distribution chart, Idemitsu Kosan Co ranks #373 out of 772 companies in the Oil & Gas industry, which is above the industry midpoint. Overall, Idemitsu Kosan Co has a GF Score™ of 68/100 and is considered Modestly Overvalued, reflecting its overall financial health beyond just this single metric.
How does Idemitsu Kosan Co's Cyclically Adjusted PB Ratio compare to VLO and MPC?
According to the Oil & Gas industry distribution chart, Idemitsu Kosan Co ranks #373 out of 772 companies for Cyclically Adjusted PB Ratio. This puts Idemitsu Kosan Co in the upper half of its industry. The industry median Cyclically Adjusted PB Ratio is 1.18. Idemitsu Kosan Co's value of 1.11 is 5.9% below this benchmark. Historically, Idemitsu Kosan Co's own Cyclically Adjusted PB Ratio has ranged from 0.54 to 1.69 over the past decade. While the company's 10-year median is 0.86 vs. the industry median of 1.18, Idemitsu Kosan Co has consistently been below the industry average. See the competitive comparison table and distribution chart on this page for a detailed peer-by-peer breakdown.
What is a good Cyclically Adjusted PB Ratio for an Oil & Gas company?
The median Cyclically Adjusted PB Ratio among Oil & Gas companies is 1.18, based on 772 companies in the industry. Companies in the top quartile (top 25%) have a Cyclically Adjusted PB Ratio significantly above this median, while those in the bottom quartile fall well below. However, Cyclically Adjusted PB Ratio should not be evaluated in isolation — investors should consider it alongside profitability, growth, and financial strength metrics. Idemitsu Kosan Co's current Cyclically Adjusted PB Ratio of 1.11 is 5.9% below the industry median. Use the industry distribution chart on this page to see where any company falls relative to its peers.
What does a high Cyclically Adjusted PB Ratio mean?
A high Cyclically Adjusted PB Ratio can signal that a stock is expensive relative to its fundamentals. Cyclically Adjusted PB Ratio is the ratio of share price to a company's inflation-adjusted book value per share over a 10-year period. View historical data on Idemitsu Kosan Co and its competitors. For the Oil & Gas industry, the median Cyclically Adjusted PB Ratio is 1.18 — values significantly above this may indicate overvaluation, while values below may suggest a bargain or underlying issues. Idemitsu Kosan Co's current Cyclically Adjusted PB Ratio is 1.11, which is 29% above median its own 10-year median of 0.86. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is Idemitsu Kosan Co stock overvalued right now?
Based on GuruFocus' analysis, Idemitsu Kosan Co (IDKOF) is currently considered Modestly Overvalued. The stock's GF Value™ is $6.74, compared to a current price of $7.50 — trading 11.3% above its estimated fair value. The current Cyclically Adjusted PB Ratio is 1.11, which is 29% above median its 10-year median of 0.86 and 5.9% below the Oil & Gas industry median of 1.18. Idemitsu Kosan Co's overall GF Score™ is 68/100 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 PB Ratio calculated?
Cyclically Adjusted PB Ratio is calculated from a company's financial statements. For Idemitsu Kosan Co (IDKOF), the current Cyclically Adjusted PB Ratio is 1.11 as of Jul. 11, 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 Idemitsu Kosan Co (IDKOF) Overvalued in 2026?
Based on GuruFocus' analysis, Idemitsu Kosan Co stock appears to be overvalued.
The current stock price of $7.50 is trading 11.3% above its estimated GF Value™ of $6.74.
GuruFocus considers Idemitsu Kosan Co to be Modestly Overvalued.
Key valuation signals for IDKOF:
Cyclically Adjusted PB Ratio: 1.11 (29% above median its 10-year median of 0.86)
GF Value™: $6.74 vs. price of $7.50 (11.3% above fair value)
Industry Position: 5.9% below the Oil & Gas median (#373 of 772)
No single metric tells the full story. See the IDKOF stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.
Idemitsu Kosan Co Ltd engages in a variety of activities globally that include petroleum products, oil exploration and production, coal, and other businesses. The company operates through five segments. The Basic Chemicals segment makes and sells olefins and aroma products. Electricity/Renewable Energy covers thermal, solar, and wind power generation, electricity sales, and solar business. Fuel Oil handles production, trading, and import/export of refined petroleum. The Highly Functional Materials segment includes lubricants, chemicals, electronic materials, paving materials, and agri-bio. The Resource segment explores, develops, and sells crude oil, natural gas, and coal. Others cover insurance and intra-group services. It generates the majority of its revenue from the Fuel oil segment.
68GF Score
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