condition mean min max ZT0-3 8.914575 8.42314 9.40601 ZT4-7 7.72224 7.72224 7.72224 ZT8-11 4.700945 4.700945 4.700945 ZT12-15 0 0 0 ZT16-19 8.82476 8.82476 8.82476 ZT20-23 10.241675 10.241675 10.241675