condition mean min max ZT0-3 17.515575 16.08725 18.9439 ZT4-7 27.0248 27.0248 27.0248 ZT8-11 21.7628 21.7628 21.7628 ZT12-15 0 0 0 ZT16-19 36.81935 36.81935 36.81935 ZT20-23 36.736850000000004 36.736850000000004 36.736850000000004