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Tan Delta SystemsLSE:TAND 25 Graham Number is £N/A as of Dec. 2025. GuruFocus rates LSE:TAND with a GF Score™ of 25/100 and a GF Value™ of £0.18 (Significantly Overvalued). The stock has 4 warning signs investors should review. Among 609 Oil & Gas companies, Tan Delta Systems ranks worse than 164203.45% on this metric.
Graham Number is a figure that measures a stock's fundamental value by taking into account the company's earnings per share and book value per share. The Graham number is the upper bound of the price range that a defensive investor should pay for the stock. According to the theory, any stock price below the Graham number is considered undervalued, and thus worth investing in.
As of today (2026-07-24), the stock price of Tan Delta Systems is £0.29. Tan Delta Systems's graham number for the quarter that ended in Dec. 2025 was £N/A. Therefore, Tan Delta Systems's Price to Graham Number ratio for today is N/A.
The historical rank and industry rank for Tan Delta Systems's Graham Number or its related term are showing as below:
LSE:TAND's Price-to-Graham-Number is not ranked *
in the Oil & Gas industry.
Industry Median: 1.13 * Ranked among companies with meaningful Price-to-Graham-Number only.
Graham Number is a combination of asset valuation and earnings power valuation. It is a very conservative way of valuing a stock.
Tan Delta Systems (LSE:TAND) Graham Number Explanation
Ben Graham actually did not publish a formula like this. But he wrote in The Intelligent Investor (1948 version) regarding to the criteria for purchases:
Current price should not be more than 15 times average earnings of the past three years.
Current price should not be more than 1.5 times the book value last reported. However, a multiplier of earnings below 15 could justify a correspondingly higher multiplier of assets. As a rule of thumb we suggest that the product of the multiplier times the ratio of price to book value should not exceed 22.5. (This figure corresponds to 15 times earnings and 1.5 times book value. It would admit an issue selling at only 9 times earnings and 2.5 times asset value, etc.)
Unlike valuation methods such as DCF or Discounted Earnings, the Graham number does not take growth into the valuation. Unlike the valuation methods based on book value alone, it takes into account the earnings power. Therefore, the Graham Number is a combination of asset valuation and earnings power valuation.
In general, the Graham number is a very conservative way of valuing a stock. It cannot be applied to companies with negative book values.
Tan Delta Systems's Price to Graham number Ratio for today is calculated as
Price to Graham number
=
Share Price (Today)
/
Graham number (Q: Dec. 2025 )
=
0.29
/
N/A
=
N/A
* 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.
Be Aware
Please keep these in mind:
1. Graham Number does not take growth into account. Therefore it underestimates the values of the companies that have good earnings growth. We feel that if the earnings per share grows more than 10% a year, Graham Number underestimates the value.
2. Graham Number punishes the companies that have temporarily low earnings. Therefore, an average of earnings makes more sense in the calculation of Graham Number.
3. Graham Numbers underestimates companies that are light with book.
Tan Delta Systems Graham Number Related Terms
Tan Delta Systems Graham Number Historical Data
* Premium members only.
The historical data trend for Tan Delta Systems's Graham Number 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.
LSE:TAND vs SLB, BKR, HAL: Graham Number Comparison
For the Oil & Gas Equipment & Services subindustry, Tan Delta Systems's Price-to-Graham-Number, along with its competitors' market caps and Price-to-Graham-Number 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.
Tan Delta Systems Price-to-Graham-Number vs Oil & Gas Industry
For the Oil & Gas industry and Energy sector, Tan Delta Systems's Price-to-Graham-Number distribution charts can be found below:
* The bar in red indicates where Tan Delta Systems's Price-to-Graham-Number falls into.
* 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.
Tan Delta Systems (LSE:TAND) has a Graham Number of £N/A as of Dec. 2025. The Graham Number values a company based on its per-share earnings and book value. View historical data on Tan Delta Systems and its competitors. According to the industry distribution chart, Tan Delta Systems ranks #999999 out of 609 companies in the Oil & Gas industry.
Is Tan Delta Systems' Graham Number too high?
Tan Delta Systems' current Graham Number is £N/A. Based on the distribution chart, Tan Delta Systems ranks #999999 out of 609 companies in the Oil & Gas industry, which is in the bottom quartile relative to peers. Overall, Tan Delta Systems has a GF Score™ of 25/100 and is considered Significantly Overvalued, reflecting its overall financial health beyond just this single metric.
How does Tan Delta Systems' Graham Number compare to SLB and BKR?
According to the Oil & Gas industry distribution chart, Tan Delta Systems ranks #999999 out of 609 companies for Graham Number. This places Tan Delta Systems in the lower half of its industry. The industry median Graham Number is 1.13. See the competitive comparison table and distribution chart on this page for a detailed peer-by-peer breakdown.
What is a good Graham Number for an Oil & Gas company?
The median Graham Number among Oil & Gas companies is 1.13, based on 609 companies in the industry. Companies in the top quartile (top 25%) have a Graham Number significantly above this median, while those in the bottom quartile fall well below. However, Graham Number 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 Graham Number mean?
A high Graham Number can signal that a stock is expensive relative to its fundamentals. The Graham Number values a company based on its per-share earnings and book value. View historical data on Tan Delta Systems and its competitors. For the Oil & Gas industry, the median Graham Number is 1.13 — values significantly above this may indicate overvaluation, while values below may suggest a bargain or underlying issues. Tan Delta Systems's current Graham Number is £N/A. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is Tan Delta Systems stock overvalued right now?
Based on GuruFocus' analysis, Tan Delta Systems (LSE:TAND) is currently considered Significantly Overvalued. The stock's GF Value™ is £0.18, compared to a current price of £0.29 — trading 61.1% above its estimated fair value. The current Graham Number is £N/A. Tan Delta Systems' overall GF Score™ is 25/100 with 4 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is Graham Number calculated?
Graham Number is calculated from a company's financial statements. For Tan Delta Systems (LSE:TAND), the current Graham Number is £N/A 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 Tan Delta Systems (LSE:TAND) Overvalued in 2026?
Based on GuruFocus' analysis, Tan Delta Systems stock appears to be overvalued.
The current stock price of £0.29 is trading 61.1% above its estimated GF Value™ of £0.18.
GuruFocus considers Tan Delta Systems to be Significantly Overvalued.
Key valuation signals for LSE:TAND:
Graham Number: £N/A
GF Value™: £0.18 vs. price of £0.29 (61.1% above fair value)
No single metric tells the full story. See the LSE:TAND stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.
Tan Delta Systems PLC develops real-time oil analysis and analytic technologies and products with capabilities that enable equipment operators to significantly reduce operating costs, improve efficiency, and reduce carbon footprint. It develops all its core technologies and products in-house, with manufacturing undertaken by its carefully selected manufacturing partners with whom its dedicated production QA department works. Its products include Sensors, Kits, Display solutions, Gateways & modems, and Accessories & services. Geographically, its solutions are in use across the UK, Europe, North and South America, Asia, and the Middle East.
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