condition mean min max ZT0-3 42.54701666666667 39.38365 46.912800000000004 ZT4-7 18.9395 18.9395 18.9395 ZT8-11 7.64911 7.64911 7.64911 ZT12-15 12.39891 8.99362 15.8042 ZT16-19 4.4314 4.4314 4.4314 ZT20-23 9.327135 9.327135 9.327135