Assessing the career performances of horses with different formlines has always been an inexact science.

One measure that most of the early ratings methods placed quite a bit of importance on was the average prizemoney per start for each horse. The theory was that the higher the average amount earned each start, the better the quality the horse.

So the API could be used before the race as a ranking measure and also post-race as an assessment of the overall class of the field.

Since many computerised ratings programs include prizemoney earned as an important yardstick, does that mean it is now another form factor that is over-exposed and over-bet?

Let’s look at the record of the SP favourite for the last four years of metropolitan racing:

It is very clear that the two highest ranked API horses were actually the least profitable. These obvious standout favourites are overbet, losing more than 5% on turnover whereas the remainder (average prizemoney rank of 3 or more) actually broke even as a group.

So let’s broaden our outlook now to include the first four in the betting market:

Again it is clear that the market over-rates the top two on earnings per start.

So are there any situations where the number one API performs well?

It does tend to be a better guide once the horses mature. The table below shows that horses aged 5 years and older lost only 2% on turnover, whereas the combined group of 2yo/3yo/4yo lost 10%:

But there were no other obvious scenarios where the API provided a solid edge and here are a few reasons why:

  • Improving horses are hard to identify
  • Weight, distance, track condition and many other form factors are ignored
  • Old form is ‘weighted’ to be as important as recent form
  • Computerised ratings systems over-rate its relative importance

Once again we have found that obvious, widely known stats are well and truly factored into the market. You need to go a little wider or even outside the box to find a winning edge.

Good luck David Duffield