condition mean min max ZT0-3 77.230639 77.230639 77.230639 ZT4-7 57.1520615 57.1520615 57.1520615 ZT8-11 61.662816 61.662816 61.662816 ZT12-15 55.479690500000004 55.479690500000004 55.479690500000004 ZT16-19 85.7589595 85.7589595 85.7589595 ZT20-23 76.421998 76.421998 76.421998