condition mean min max ZT0-3 8.25534 8.25534 8.25534 ZT4-7 9.1962265 9.1962265 9.1962265 ZT8-11 8.9804475 8.9804475 8.9804475 ZT12-15 8.996876 8.996876 8.996876 ZT16-19 10.265503500000001 10.265503500000001 10.265503500000001 ZT20-23 33.6602025 33.6602025 33.6602025