condition mean min max ZT0-3 44.997053 44.997053 44.997053 ZT4-7 15.642827 15.642827 15.642827 ZT8-11 11.092126 11.092126 11.092126 ZT12-15 11.702615 11.702615 11.702615 ZT16-19 10.267745999999999 10.267745999999999 10.267745999999999 ZT20-23 10.119446 10.119446 10.119446