condition mean min max ZT0-3 13.693675 13.693675 13.693675 ZT4-7 13.055731999999999 13.055731999999999 13.055731999999999 ZT8-11 12.491763500000001 12.491763500000001 12.491763500000001 ZT12-15 12.3975205 12.3975205 12.3975205 ZT16-19 12.7130835 12.7130835 12.7130835 ZT20-23 12.185599 12.185599 12.185599