condition mean min max ZT0-3 25.391 25.391 25.391 ZT4-7 18.10585 18.10585 18.10585 ZT8-11 13.1173 13.1173 13.1173 ZT12-15 11.478685 11.478685 11.478685 ZT16-19 16.001350000000002 16.001350000000002 16.001350000000002 ZT20-23 19.219 19.219 19.219