condition mean min max ZT0-3 11.399999999999999 11.399999999999999 11.399999999999999 ZT4-7 4.6 4.6 4.6 ZT8-11 34.15 34.15 34.15 ZT12-15 9.7 9.7 9.7 ZT16-19 13.600000000000001 13.600000000000001 13.600000000000001 ZT20-23 19.05 19.05 19.05