condition mean min max ZT0-3 7.497769999999999 2.619655 16.93565 ZT4-7 11.287485 11.287485 11.287485 ZT8-11 19.64595 19.64595 19.64595 ZT12-15 5.836947500000001 2.66007 9.013825 ZT16-19 1.269685 1.269685 1.269685 ZT20-23 1.068743 1.068743 1.068743