condition mean min max ZT0-3 6.841809 6.841809 6.841809 ZT4-7 6.9501865 6.9501865 6.9501865 ZT8-11 6.939582 6.939582 6.939582 ZT12-15 6.7529795 6.7529795 6.7529795 ZT16-19 6.784561500000001 6.784561500000001 6.784561500000001 ZT20-23 10.0145835 10.0145835 10.0145835