condition mean min max ZT0-3 17.01815 17.01815 17.01815 ZT4-7 15.77075 15.77075 15.77075 ZT8-11 12.41235 12.41235 12.41235 ZT12-15 8.289915 8.289915 8.289915 ZT16-19 12.61545 12.61545 12.61545 ZT20-23 17.37295 17.37295 17.37295