condition mean min max ZT0-3 9.8 9.8 9.8 ZT4-7 52.4 52.4 52.4 ZT8-11 65.15 65.15 65.15 ZT12-15 15.3 15.3 15.3 ZT16-19 54.150000000000006 54.150000000000006 54.150000000000006 ZT20-23 18.95 18.95 18.95