condition mean min max ZT0-3 51.650000000000006 51.650000000000006 51.650000000000006 ZT4-7 37.6 37.6 37.6 ZT8-11 43.4 43.4 43.4 ZT12-15 48.5 48.5 48.5 ZT16-19 59.150000000000006 59.150000000000006 59.150000000000006 ZT20-23 32.55 32.55 32.55