condition mean min max ZT0-3 8.102993333333332 6.70514 9.008424999999999 ZT4-7 2.87652 2.87652 2.87652 ZT8-11 1.251865 1.251865 1.251865 ZT12-15 1.1823375 1.15432 1.2103549999999998 ZT16-19 1.266415 1.266415 1.266415 ZT20-23 3.0968600000000004 3.0968600000000004 3.0968600000000004