condition mean min max ZT0-3 17.898962 17.898962 17.898962 ZT4-7 25.0791855 25.0791855 25.0791855 ZT8-11 14.670385 14.670385 14.670385 ZT12-15 12.7265965 12.7265965 12.7265965 ZT16-19 12.0237025 12.0237025 12.0237025 ZT20-23 13.860905500000001 13.860905500000001 13.860905500000001