condition mean min max ZT0-3 6.758888889 6.758888889 6.758888889 ZT4-7 7.938888889 7.938888889 7.938888889 ZT8-11 6.465 6.465 6.465 ZT12-15 5.3100000000000005 5.3100000000000005 5.3100000000000005 ZT16-19 4.314444444333334 4.314444444333334 4.314444444333334 ZT20-23 5.184444444333334 5.184444444333334 5.184444444333334