condition mean min max ZT0-3 9.083257499999998 8.832495 9.334019999999999 ZT4-7 8.157555 8.157555 8.157555 ZT8-11 27.60035 27.60035 27.60035 ZT12-15 0 0 0 ZT16-19 19.9503 19.9503 19.9503 ZT20-23 14.0836 14.0836 14.0836