condition mean min max ZT0-3 9.5330475 9.34948 9.716615000000001 ZT4-7 6.410410000000001 6.410410000000001 6.410410000000001 ZT8-11 8.27047 8.27047 8.27047 ZT12-15 0 0 0 ZT16-19 11.07055 11.07055 11.07055 ZT20-23 10.79645 10.79645 10.79645