condition mean min max ZT0-3 12.51695 12.51695 12.51695 ZT4-7 15.143450000000001 15.143450000000001 15.143450000000001 ZT8-11 9.593499999999999 9.593499999999999 9.593499999999999 ZT12-15 8.68405 8.68405 8.68405 ZT16-19 6.844374999999999 6.844374999999999 6.844374999999999 ZT20-23 7.07898 7.07898 7.07898