condition mean min max ZT0-3 16.216925 15.643650000000001 16.7902 ZT4-7 22.98415 22.98415 22.98415 ZT8-11 32.6987 32.6987 32.6987 ZT12-15 0 0 0 ZT16-19 32.9283 32.9283 32.9283 ZT20-23 24.3919 24.3919 24.3919