condition mean min max ZT0-3 5.24696222225 4.1131909460000005 6.3807334985 ZT4-7 4.521255495 3.8278530799999997 5.21465791 ZT8-11 5.237561714 4.5526254385 5.9224979895 ZT12-15 3.5362162757499997 2.9094781055 4.162954446 ZT16-19 2.2442903395 2.025546618 2.463034061 ZT20-23 4.302806274 3.47958163 5.126030918