condition mean min max ZT0-3 9.39339 8.53883 10.24795 ZT4-7 6.054535 6.054535 6.054535 ZT8-11 6.670495000000001 6.670495000000001 6.670495000000001 ZT12-15 0 0 0 ZT16-19 8.207805 8.207805 8.207805 ZT20-23 6.944155 6.944155 6.944155