condition mean min max ZT0-3 63.029369 63.029369 63.029369 ZT4-7 77.58465899999999 77.58465899999999 77.58465899999999 ZT8-11 81.297534 81.297534 81.297534 ZT12-15 83.94939450000001 83.94939450000001 83.94939450000001 ZT16-19 86.4918835 86.4918835 86.4918835 ZT20-23 65.1472695 65.1472695 65.1472695