condition mean min max ZT0-3 19134.26506 19134.26506 19134.26506 ZT4-7 17203.83298 17203.83298 17203.83298 ZT8-11 17357.721064999998 17357.721064999998 17357.721064999998 ZT12-15 16485.51822 16485.51822 16485.51822 ZT16-19 15319.8633 15319.8633 15319.8633 ZT20-23 15349.200550000001 15349.200550000001 15349.200550000001