condition mean min max ZT0-3 6.303725 6.303725 6.303725 ZT4-7 4.30842 4.30842 4.30842 ZT8-11 3.816835 3.816835 3.816835 ZT12-15 5.012639999999999 5.012639999999999 5.012639999999999 ZT16-19 6.855255 6.855255 6.855255 ZT20-23 6.90067 6.90067 6.90067