condition mean min max ZT0-3 2.153665 2.153665 2.153665 ZT4-7 1.321404 1.321404 1.321404 ZT8-11 1.6242 1.6242 1.6242 ZT12-15 2.835 2.835 2.835 ZT16-19 2.617595 2.617595 2.617595 ZT20-23 4.047385 4.047385 4.047385