condition mean min max ZT0-3 9.35181 9.35181 9.35181 ZT4-7 9.340133999999999 9.340133999999999 9.340133999999999 ZT8-11 8.5914795 8.5914795 8.5914795 ZT12-15 8.9007535 8.9007535 8.9007535 ZT16-19 9.634116 9.634116 9.634116 ZT20-23 9.975751 9.975751 9.975751