condition mean min max ZT0-3 14.5169 10.58 18.4538 ZT4-7 8.27268 8.27268 8.27268 ZT8-11 5.1511 5.1511 5.1511 ZT12-15 0 0 0 ZT16-19 7.48902 7.48902 7.48902 ZT20-23 7.531335 7.531335 7.531335