condition mean min max ZT0-3 4.5952874999999995 4.12273 5.067845 ZT4-7 9.92031 9.92031 9.92031 ZT8-11 7.09274 7.09274 7.09274 ZT12-15 0 0 0 ZT16-19 6.189565 6.189565 6.189565 ZT20-23 5.843154999999999 5.843154999999999 5.843154999999999