Player Clan War History is only stored when someone in your clan either checks their profile or someone checks the War Stats page for a clan that you were in recently or are currently in.
The data for Decks Used wasn't available until 2/15/21, so every Race before that will show 0 Decks Used.
Player Clan War History is only stored when someone in your clan either checks their profile or someone checks the War Stats page for a clan that you were in recently or are currently in.