As mentioned already, horses are rated on a pound scale from 0 (zero) to 140. The internationally accepted parameter for a Group or Grade One performer is a rating of 120 or 115 depending on where the racing takes place, while for a Group or Grade Two it is 115 or 110, and for a Group or Grade Three it is 110 or 105. Listed races are generally accepted as being 105/100 or below.
From the above information, it is possible to work out where the remaining races in the calendar fit into the 0-140 scale. Given that there are more moderate horses in the 0 to 40 bracket than horses rated between 100 to 140, the average on most handicap files would be between 60 and 70.
In the UK, a maiden (a horse that has never won a race) with a rating of 70 would be considered unfortunate not to have hit the target by the end of the season if he were competing in maiden events at one of the smaller racetracks. On the other hand, if he were campaigned in maidens at, say, Newmarket or Newbury he would find it difficult to be competitive, as on average the winner at those tracks would probably be rated 85 to 95.
A horse rated 85 would almost certainly be confined to racing in handicaps for the remainder of his career but would also be competitive in conditions races (base weight, plus extra weight incurred for having won a race or races) at a minor racetrack.
A horse with a rating of 95 would again be likely to run in handicaps but could also be competitive in conditions race at the better race meetings. He would also be worth entering in Listed events in the hope that the opposition was not too strong.
Horses rated 60 or below would struggle to be competitive even in maidens at the minor racetracks and would probably have to race in the lowest-rated handicaps, auction races, claiming races or selling races.