condition mean min max ZT0-3 2.4933595735000003 1.8390570990000001 3.147662048 ZT4-7 4.79584917675 3.8723057645 5.719392589 ZT8-11 7.341910779250001 6.190998403 8.492823155500002 ZT12-15 9.67181180775 8.614999833 10.7286237825 ZT16-19 4.733760397749999 4.438511869499999 5.0290089259999995 ZT20-23 8.012338251749998 6.9529285965 9.071747906999999