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Subject:  Re: SI Rankings 2020-08-07 Date:  8/9/2020  5:00 PM
Author:  FLARAM Number:  278644 of 281961

When we rank the so called SI-Pro screens in GTR1, we aren't really running SI-Pro screens.

I wouldn’t express it quite so strongly. GTR1 is using both the current and historical SI-Pro data which they published from 1997. Unfortunately, the AAII people don’t seem to be all that concerned with the consistency of their fundamental data fields. Every couple of years they arbitrarily drop a few fields, create a few new ones and then change the way they calculate a couple. They even once changed all the company id numbers that over time distinguished between using identical tickers mnemonics. Only members of this board who are actually measuring how well this data has corresponded to profits seem to notice these changes.

Robbie has been doing an unbelievably difficult job of working around these changes, recalculating the fields where necessary and linking other data sources to the data. The most amazing part of this is that as I understand it he was a mathematician when he started with very little programming or finance skills.
. . . And yes Robbie does all the work! I don’t even believe we are paying for his computer or internet access.

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