condition mean min max ZT0-3 8.98794 8.05202 9.92386 ZT4-7 8.286915 8.286915 8.286915 ZT8-11 7.95714 7.95714 7.95714 ZT12-15 0 0 0 ZT16-19 8.39475 8.39475 8.39475 ZT20-23 6.8908450000000006 6.8908450000000006 6.8908450000000006