condition mean min max ZT0-3 20.85335 20.85335 20.85335 ZT4-7 9.513964999999999 9.513964999999999 9.513964999999999 ZT8-11 10.675315000000001 10.675315000000001 10.675315000000001 ZT12-15 13.611 13.611 13.611 ZT16-19 24.45675 24.45675 24.45675 ZT20-23 18.3116 18.3116 18.3116