condition mean min max ZT0-3 7.200175 6.967180000000001 7.483175 ZT4-7 3.610275 3.610275 3.610275 ZT8-11 3.06827 3.06827 3.06827 ZT12-15 5.100714999999999 4.7456499999999995 5.45578 ZT16-19 4.55278 4.55278 4.55278 ZT20-23 5.10226 5.10226 5.10226