condition mean min max ZT0-3 10.617085 10.05227 11.1819 ZT4-7 18.8018 18.8018 18.8018 ZT8-11 26.1261 26.1261 26.1261 ZT12-15 0 0 0 ZT16-19 26.276249999999997 26.276249999999997 26.276249999999997 ZT20-23 18.844250000000002 18.844250000000002 18.844250000000002