About the Numbers:
The PPN is the Projected Power Number

Each horse is rated as if it ran alone, getting a decent trip without any unexpected problems.

The PPN is a HARD number for the horse to achieve and should do so approximately 1/3 of the time.

The ratings are based on the INTERNAL and FINAL TIME SPEED FIGURES published in Jerry J’s Performance Pages.

The ratings are closely related to the most recent races a horse has run. Strict limitations are applied to the projections allowing the player to use them in conjunction with their preferred past performance material.

Horses returning from a layoff are conservatively “pegged.” (Maybe we should simply say — downgraded)

It makes perfect sense for you to adjust the PPN’s; here are a few ideas:

If you think the expected trip will be poor then adjust the horse’s PPN down.
If you think the post position is a big negative then adjust the horse’s PPN down.
If you believe a track bias exists and it will benefit your horse then increase the PPN slightly—decrease the PPN significantly if you believe it will be negative.
The PPN for a European shipper is approximate in nature since it is based on comparisons and pars.