condition mean min max ZT0-3 348.244629 348.244629 348.244629 ZT4-7 310.53114949999997 310.53114949999997 310.53114949999997 ZT8-11 316.01816899999994 316.01816899999994 316.01816899999994 ZT12-15 341.75910350000004 341.75910350000004 341.75910350000004 ZT16-19 302.6353335 302.6353335 302.6353335 ZT20-23 248.6195595 248.6195595 248.6195595