condition mean min max ZT0-3 12.6239775 9.674955 15.573 ZT4-7 34.11335 34.11335 34.11335 ZT8-11 62.73965 62.73965 62.73965 ZT12-15 0 0 0 ZT16-19 60.48725 60.48725 60.48725 ZT20-23 31.876649999999998 31.876649999999998 31.876649999999998