condition mean min max ZT0-3 31.143509 31.143509 31.143509 ZT4-7 62.730249 62.730249 62.730249 ZT8-11 116.025857 116.025857 116.025857 ZT12-15 188.837999 188.837999 188.837999 ZT16-19 118.5301455 118.5301455 118.5301455 ZT20-23 189.469626 189.469626 189.469626