condition mean min max ZT0-3 1.189684835 1.0068433909999999 1.3725262790000001 ZT4-7 2.63613870125 1.749845529 3.5224318735 ZT8-11 5.2550352595 4.4972467285 6.012823790499999 ZT12-15 8.9697377475 6.4669750195 11.4725004755 ZT16-19 7.279732446 6.491836804 8.067628088 ZT20-23 10.118246905749999 9.126516361499998 11.109977449999999