condition mean min max ZT0-3 14.994966666666667 11.9858 18.41465 ZT4-7 10.01725 10.01725 10.01725 ZT8-11 9.803065 9.803065 9.803065 ZT12-15 16.950375 15.9773 17.923450000000003 ZT16-19 13.7442 13.7442 13.7442 ZT20-23 19.83265 19.83265 19.83265