condition mean min max ZT0-3 338.123871 338.123871 338.123871 ZT4-7 260.537779 260.537779 260.537779 ZT8-11 322.39925500000004 322.39925500000004 322.39925500000004 ZT12-15 347.2810115 347.2810115 347.2810115 ZT16-19 439.74486349999995 439.74486349999995 439.74486349999995 ZT20-23 1392.556443 1392.556443 1392.556443