condition mean min max ZT0-3 7.6370989565 6.945161227 8.329036686 ZT4-7 4.435481394 4.2537816555 4.6171811325 ZT8-11 7.70156158725 5.394492774000001 10.0086304005 ZT12-15 8.661306909250001 8.5375348805 8.785078938 ZT16-19 5.54822797375 5.3855837575 5.71087219 ZT20-23 5.4197211695 5.0657516195 5.773690719499999