condition mean min max ZT0-3 11.650894 11.650894 11.650894 ZT4-7 13.2347435 13.2347435 13.2347435 ZT8-11 13.7003315 13.7003315 13.7003315 ZT12-15 13.215282 13.215282 13.215282 ZT16-19 13.469446 13.469446 13.469446 ZT20-23 13.796723 13.796723 13.796723