Fundamental: Graham Number

$$\text{Graham Number} = \sqrt{22.5 \times EPS \times BVPS}$$

The Graham Number, from Benjamin Graham's The Intelligent Investor, estimates the maximum price a defensive value investor should pay for a stock, combining earnings power (EPS) and balance-sheet strength (book value per share) into a single fair-value benchmark.

EPS	BVPS	Graham Number
6.13	4.25	24.21
6.42	4.40	25.21

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Interpreting the Result

Compare the Graham Number against the current market price (an Alpaca closing price, for example) with a Subtract or Divide module:

Comparison	Reading
Price well below Graham Number	Potentially undervalued by Graham's criterion
Price near Graham Number	Fairly valued
Price well above Graham Number	Potentially overvalued

The Graham Number is a single point-in-time benchmark, not a band — pair it with your own margin-of-safety threshold.

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Missing Data

If either EPS or book value per share is missing (null) at a position, the Graham Number at that position is null.

The formula is also undefined — and therefore null — whenever EPS or BVPS is negative. That includes the case where both are negative: their product is positive, but a company with negative earnings and negative book value is un-investable by Graham's own criterion, so no number is emitted. The module never forces a value out of an undefined case; a negative input stays null, exactly like any other undefined result.

EPS	BVPS	Result
null	4.25	null
6.13	null	null
-1.5	3.00	null (negative earnings)
-2.0	-5.0	null (both negative — never a fabricated value)
6.13	4.25	24.21

In live execution the module returns exactly one datapoint — the newest position — which is null when it cannot be determined.

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Wiring

Wire both inputs from the Stock: Fundamentals node:

• eps → EPS input (trailing-twelve-month earnings per share)
• bvps → Book Value Per Share input

EPS is a trailing-twelve-month rollup and Book Value per Share is a point-in-time quarter-end balance — Stock: Fundamentals already assembles both, so no additional TTM work or wiring is required from you.

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Related Modules

• ALTZ — Altman Z-Score (bankruptcy risk)
• PFS — Piotroski F-Score (fundamental quality)