condition mean min max ZT0-3 0.0 0.0 0.0 ZT4-7 0.0 0.0 0.0 ZT8-11 3.6601715095000005 0.0 7.320343019000001 ZT12-15 4.103406219833333 0.0 8.206812439666667 ZT16-19 1.4784691286666667 1.3076181896666665 1.6493200676666666 ZT20-23 1.7744380925 1.641717535 1.9071586500000002