condition mean min max ZT0-3 7.720610181 6.831638904 8.609581458 ZT4-7 7.7081959335 7.161416911 8.254974956 ZT8-11 10.2747489465 8.296402382 12.253095511 ZT12-15 9.8180495255 9.698362588999998 9.937736462 ZT16-19 9.49186086675 9.229746287000001 9.7539754465 ZT20-23 10.17152483075 10.1206995 10.2223501615