condition mean min max ZT0-3 191.773872 191.773872 191.773872 ZT4-7 89.50368700000001 89.50368700000001 89.50368700000001 ZT8-11 84.41938 84.41938 84.41938 ZT12-15 109.4315845 109.4315845 109.4315845 ZT16-19 211.525332 211.525332 211.525332 ZT20-23 183.69658349999997 183.69658349999997 183.69658349999997