condition mean min max ZT0-3 12.3513 12.3513 12.3513 ZT4-7 7.626405 7.626405 7.626405 ZT8-11 7.884875 7.884875 7.884875 ZT12-15 9.615685 9.615685 9.615685 ZT16-19 14.950199999999999 14.950199999999999 14.950199999999999 ZT20-23 14.364799999999999 14.364799999999999 14.364799999999999