condition mean min max ZT0-3 5.3065344432499995 5.200837429 5.412231457499999 ZT4-7 7.6925809659999995 7.4421420755 7.9430198565 ZT8-11 11.8169768935 9.9133150595 13.720638727499999 ZT12-15 18.525420975 18.484984224999998 18.565857725 ZT16-19 18.1321779475 17.101473390000002 19.162882505 ZT20-23 15.352295832500001 15.279121320000002 15.425470345