condition mean min max ZT0-3 16.96588 13.15176 20.78 ZT4-7 7.842955 7.842955 7.842955 ZT8-11 6.46583 6.46583 6.46583 ZT12-15 0 0 0 ZT16-19 9.30692 9.30692 9.30692 ZT20-23 9.862345000000001 9.862345000000001 9.862345000000001