condition mean min max ZT0-3 17.3 17.3 17.3 ZT4-7 44.3 44.3 44.3 ZT8-11 45.0 45.0 45.0 ZT12-15 19.8 19.8 19.8 ZT16-19 19.450000000000003 19.450000000000003 19.450000000000003 ZT20-23 11.5 11.5 11.5