condition mean min max ZT0-3 10.352360000000001 9.86547 10.83925 ZT4-7 6.2268 6.2268 6.2268 ZT8-11 6.578615 6.578615 6.578615 ZT12-15 0 0 0 ZT16-19 7.865295 7.865295 7.865295 ZT20-23 9.29542 9.29542 9.29542