condition mean min max ZT0-3 494.643605 494.643605 494.643605 ZT4-7 711.3067885 711.3067885 711.3067885 ZT8-11 451.84431900000004 451.84431900000004 451.84431900000004 ZT12-15 441.6819835 441.6819835 441.6819835 ZT16-19 264.441301 264.441301 264.441301 ZT20-23 257.99008349999997 257.99008349999997 257.99008349999997