condition mean min max ZT0-3 63.006931 63.006931 63.006931 ZT4-7 160.229823 160.229823 160.229823 ZT8-11 127.061206 127.061206 127.061206 ZT12-15 103.526657 103.526657 103.526657 ZT16-19 84.4382315 84.4382315 84.4382315 ZT20-23 47.4964945 47.4964945 47.4964945