condition mean min max ZT0-3 28.44036 28.44036 28.44036 ZT4-7 25.4242305 25.4242305 25.4242305 ZT8-11 26.548404 26.548404 26.548404 ZT12-15 25.6459935 25.6459935 25.6459935 ZT16-19 24.0944575 24.0944575 24.0944575 ZT20-23 24.556829999999998 24.556829999999998 24.556829999999998