The user in this discussion makes a very valid point that Graham recommended a P/E ratio no higher than 13.3 against an AA bond yield of 7.5%. Based on that principle, a defensive investor today should consider stocks with P/E < 37.17 since 10-year AA corporate bond yields as of 03/23/2015 are 2.69%.
Adjusting Graham's criteria to screen Defensive grade stocks with P/E ratios of 37 (all else being equal) on Serenity would involve the following:
37÷15 = 2.467
√2.467 = 1.57
We would need to multiply the Graham Number of a stock by 1.57 to adjust it to a maximum PE of 37.
Serenity's default Graham analyses and the Classic Graham Screener use Graham's recommended numbers for the analysis. But the Advanced Graham Screener can be used to screen stocks meeting the adjusted figures.
As an example, the filter values for finding Defensive quality stocks adjusted to a P/E of 37 would be:
Graham Grade: Defensive
Intrinsic Value(%) > 64%
64% is used for the Quantitative Result because the reciprocal of 1.57 is 0.6367, or 63.67%.
For Defensive quality stocks, the Intrinsic Value = Graham Number.
Prices for Enterprising and NCAV (Net-Net) grade stocks can be adjusted similarly as well.