it mentions it in the patch notes, if I recall its .8% loss per 3.8% that you got previously (equal to a single pce bonus worth of crit). This ofcourse not accounting for the scaling of crit as you stack it up.
Reduced the amount of Critical Chance Rating granted per set bonus to 657 (3%), down from 833 (3.8%). This means all sets and passives that granted Critical Rating have been adjusted to meet this new standard. All singular line stat bonuses have been adjusted to this value, while more specific adjustments will be called out below...
Spoiler
Previously, Critical Chance was sourced very abundantly and was the clear winner in terms of a chasable stat for end game damage dealing in PvE, while having natural counters and operational costs in PvP. The main source of this issue was the fact that the standard rating of Critical Chance granted was too high, meaning item sets and passives that granted it were out of line when compared to other stats like Weapon and Spell Damage, or Penetration. With these adjustments, we expect many builds to have reduced Critical Chance rating, while also helping tone down the effectiveness of Critical Damage and Healing, unless your build goes out of its way to specifically chase those stats now. https://forums.elderscrollsonline.com/en/discussion/559360/pts-patch-notes-v6-3-0#latest