Generation length essentially measures the amount of time it takes a generation to renew itself. On this website the generation length value you will see is based on the most basic definition: generation length is simply the average age of parents at the time their offspring was born. For our breed, generation length has been hovering around 4-5 years for most of its history.
A hidden value called generation births is calculated using current generation length. This value is compared to each individual’s offspring numbers in 1st, 2nd and 3rd generation. Varying generation lengths and numbers of puppies born in different years is the reason why different individuals can have different proportional contributions even if their offspring numbers are the same.
Any view with the term generation ancestor refers to an individual that appears in any 3 generation pedigree of dogs born during the latest generation (typically 4-5 years).
E.g. In 2022, a generation ancestor is any dog whose [last appearance] was ≥2017.