condition mean min max ZT0-3 7.828953333333334 5.480955 9.823875000000001 ZT4-7 2.901395 2.901395 2.901395 ZT8-11 4.47294 4.47294 4.47294 ZT12-15 5.324317499999999 5.19056 5.458074999999999 ZT16-19 6.15989 6.15989 6.15989 ZT20-23 10.17476 10.17476 10.17476