condition mean min max ZT0-3 51.150000000000006 51.150000000000006 51.150000000000006 ZT4-7 54.4 54.4 54.4 ZT8-11 57.95 57.95 57.95 ZT12-15 59.6 59.6 59.6 ZT16-19 74.6 74.6 74.6 ZT20-23 65.4 65.4 65.4