condition mean min max ZT0-3 2.6561516666666667 2.0955500000000002 3.003625 ZT4-7 1.398250002653225 1.398250002653225 1.398250002653225 ZT8-11 1.718435 1.718435 1.718435 ZT12-15 1.6064485 1.100222 2.112675 ZT16-19 2.770575 2.770575 2.770575 ZT20-23 2.81084 2.81084 2.81084