condition mean min max ZT0-3 17.68392833333333 9.603485 25.10355 ZT4-7 3.69577 3.69577 3.69577 ZT8-11 4.92211 4.92211 4.92211 ZT12-15 13.084785 9.96792 16.20165 ZT16-19 11.9817 11.9817 11.9817 ZT20-23 12.71295 12.71295 12.71295