condition mean min max ZT0-3 0.591566 0.591566 0.591566 ZT4-7 0.7994684999999999 0.7994684999999999 0.7994684999999999 ZT8-11 0.3259795 0.3259795 0.3259795 ZT12-15 0.7026939999999999 0.7026939999999999 0.7026939999999999 ZT16-19 1.193834 1.193834 1.193834 ZT20-23 0.7760442666666667 0.7760442666666667 0.7760442666666667