I am guessing that the first 2 numbers are referring to males who participate in open and champion class and the next 2, for females who participte in the same classes.
So, in our case when they say "16 Yorkshire Terriers 6-5-5-0"
it means that there are :
6 males in open class
5 males in champion class
5 females in open class
0 females in champion class
As you can see Junior, puppies and veterans are separately mentioned before.
Good luck to the participants and have fun
Actually no Mike, the way we do it here, 6 Class Males of all ages - will be sorted into their various age classes, but they only give the total of all Class Males entered, 5 Female Class dogs again sorted into their age class, then there are 5 Male Champions entered and no Female Champions.
The judging schedule is an overview summary of the number of dogs entered in any one show. The divisor is Class dogs then Champion dogs. Males are always recorded first, then females = the total number of Class Dogs entered, then for the Champions - Males/Females.
The catalogue which you purchase when you arrive; will show you how the Class dogs break out by age class, and of course the owner, breeder, sire/dam etc of each dog entered.