Since December 2024 release, the French proofs had an important change. The sire calving ease , calving abilities of daughters and vitality indexes have been changed. They were usually expressed as a percentage and are now expressed centred with a genetic standard deviation of 1,with a basis between -2 and +2.
This new expression, made possible by the single step method, has the main advantage to be more accurate. Previously bulls having the same 90% proof could be different to each other, for example, some were closer to 89% so -0.4,some others were closer to 91% which is translated by +0.4 in the new system.