condition mean min max ZT0-3 17.21015 17.21015 17.21015 ZT4-7 13.3479 13.3479 13.3479 ZT8-11 18.3044 18.3044 18.3044 ZT12-15 22.80955 22.80955 22.80955 ZT16-19 31.1537 31.1537 31.1537 ZT20-23 22.7207 22.7207 22.7207