The following table shows the class structure and associated class weights and levels used with '2005 horse races' data base.

Classes with '2005 horse races' database
Class acronymDescriptionClass weight
Class levelFillies/mares
discount (kgs)
OPN QUOpen quality (Group)6773
OPN SPOpen sprint6563
OPN DSOpen distance6063
WEL NRWelter or transition to open class5653
F&M QUF&M quality (Group)5550
F&M NRF&M listed5440
3Y+ NR3yos+ open (no other restrictions)5853
3Y+ R23yos+ with 2 metrop wins (or equiv)5333
3Y+ R13yos+ with 1 metrop wins (or equiv)5223
3Y+ R03yos+ with 0 metrop wins (or equiv)4813
3YO QU3yo quality (Group)54-5842
3YO NR3yo open (no other restrictions)54-5832
3YO R23yo with 2 metrop wins (or equiv)47-4932
3YO R13yo with 1 metrop wins (or equiv)47-4922
3YO R03yo with 0 metrop wins (or equiv)37-4812
2YO QU2yo quality (Group)44-5420
2YO NR2yo open (no other restrictions)40-4820
2YO R22yo with 2 metrop wins (or equiv)40-4820
2YO R12yo with 1 metrop wins (or equiv)40-4820
2YO R02yo with 0 metrop wins (or equiv)35-5110
C6Class 65023
C5Class 54913
C4Class 44613
C3Class 34613
C2Class 24403
C1Class 14303

Notes to table:

  1. 3yo and 2yo classes have ranges of class weights over horses' year (from August to July the following year) specified in a format comprising: August class weight in kgms followed by a hyphen followed by the class weight in kgms for July the following year. The difference between lower and upper bounds of each range, rounded to nearest 0.25kg, is spread evenly month-by-month across the year and added to August value.
  2. The optimised upper end of the 2YO R0 range is higher than that for 2YO R1 and 2YO R2 classes perhaps reflecting the quality spread of horses starting racing as 2yos.