condition mean min max ZT0-3 2.4274557674999997 2.294421258 2.560490277 ZT4-7 2.032293106 1.5728692585 2.4917169535 ZT8-11 2.8215362015 2.510225287 3.1328471159999998 ZT12-15 2.42480101 2.3851394079999997 2.464462612 ZT16-19 3.5276195427499997 2.652758887 4.402480198499999 ZT20-23 7.33871027675 6.663561414 8.0138591395