condition mean min max ZT0-3 21.375925000000002 20.75215 21.9997 ZT4-7 16.45445 16.45445 16.45445 ZT8-11 12.677399999999999 12.677399999999999 12.677399999999999 ZT12-15 0 0 0 ZT16-19 19.99745 19.99745 19.99745 ZT20-23 18.5939 18.5939 18.5939