condition mean min max ZT0-3 11.5968 11.5968 11.5968 ZT4-7 13.216953333333334 13.216953333333334 13.216953333333334 ZT8-11 13.281028000000001 13.281028000000001 13.281028000000001 ZT12-15 12.52835 12.52835 12.52835 ZT16-19 13.7299 13.7299 13.7299 ZT20-23 21.06355 21.06355 21.06355