condition mean min max ZT0-3 2.8545949999999998 2.42142 3.28777 ZT4-7 5.007675 5.007675 5.007675 ZT8-11 6.34122 6.34122 6.34122 ZT12-15 0 0 0 ZT16-19 6.53453 6.53453 6.53453 ZT20-23 4.4719750000000005 4.4719750000000005 4.4719750000000005