condition mean min max ZT0-3 12.05515 12.05515 12.05515 ZT4-7 8.115995 8.115995 8.115995 ZT8-11 12.080400000000001 12.080400000000001 12.080400000000001 ZT12-15 13.4004 13.4004 13.4004 ZT16-19 17.11545 17.11545 17.11545 ZT20-23 14.8139 14.8139 14.8139