condition mean min max ZT0-3 27.53485 27.53485 27.53485 ZT4-7 21.12915 21.12915 21.12915 ZT8-11 19.84135 19.84135 19.84135 ZT12-15 24.22225 24.22225 24.22225 ZT16-19 32.53105 32.53105 32.53105 ZT20-23 27.337600000000002 27.337600000000002 27.337600000000002