condition mean min max ZT0-3 19.623025 19.62195 19.6241 ZT4-7 24.44045 24.44045 24.44045 ZT8-11 16.9416 16.9416 16.9416 ZT12-15 0 0 0 ZT16-19 12.2941 12.2941 12.2941 ZT20-23 21.111600000000003 21.111600000000003 21.111600000000003