condition mean min max ZT0-3 19.945502885 19.24663362 20.64437215 ZT4-7 28.259023659999997 28.08906192 28.4289854 ZT8-11 38.2084832525 29.158523849999998 47.258442655 ZT12-15 43.5170882225 33.796120795 53.23805565 ZT16-19 28.1512443875 23.474332229999998 32.828156545 ZT20-23 43.89946365 32.86800921 54.93091809