The base value for each individual animal changes only when the animal moves to another category.
When the base value for a category changes, the animals in that category retain the old base value until they move to the next category.
Suppose that the Farmers decided to change the base value of the Cow category to $1,000 in the second year.
The farm accountant determines the total base value for a group by multiplying the number of animals in each group by the group's base value at the end of the year.
The base value for each group of animals changes when the group of animals moves to another category.
When base value for a category changes, all of the animals in that category have the new base value.
To calculate the change in value due to change in base values, the number of animals in each category affected by the change in base values is multiplied by the change in the base value.
The base value for the Cow category increased by $100.
Each animal or group has a base value for the adult age group.
The base value for each individual animal or group does not change due to age progression because the animals do not move into additional categories.
In the individual animal approach, only new individual animals that enter the changed category have the new base value.
In the group value approach, all of the animals have the new base value.