condition mean min max ZT0-3 6.709217499999999 3.863995 9.55444 ZT4-7 8.65966 8.65966 8.65966 ZT8-11 3.84702 3.84702 3.84702 ZT12-15 0 0 0 ZT16-19 18.0398 18.0398 18.0398 ZT20-23 8.61093 8.61093 8.61093