condition mean min max ZT0-3 15.650275 13.974250000000001 17.3263 ZT4-7 6.351255 6.351255 6.351255 ZT8-11 4.85285 4.85285 4.85285 ZT12-15 0 0 0 ZT16-19 10.302145 10.302145 10.302145 ZT20-23 13.148900000000001 13.148900000000001 13.148900000000001