We have DXY, the dollar index, and JXY for Yen, EXY for Euro, CXY for CAD, BXY for pound. Since I watch USD/CNH, I decide to make my own index for yuan.
From Black Monday (the original one in the last century), BM I & II (2020, COVID), to flash crashes, bear markets that last over 1 year, failure of systems, aftermath of air disasters all fascinate me.