condition mean min max ZT0-3 231.503097 231.503097 231.503097 ZT4-7 219.3243705 219.3243705 219.3243705 ZT8-11 250.20216699999997 250.20216699999997 250.20216699999997 ZT12-15 304.832473 304.832473 304.832473 ZT16-19 269.130748 269.130748 269.130748 ZT20-23 191.14933150000002 191.14933150000002 191.14933150000002