condition mean min max ZT0-3 6.5194625 6.246665 6.792260000000001 ZT4-7 5.236219999999999 5.236219999999999 5.236219999999999 ZT8-11 4.407135 4.407135 4.407135 ZT12-15 0 0 0 ZT16-19 5.1216349999999995 5.1216349999999995 5.1216349999999995 ZT20-23 5.09188 5.09188 5.09188