condition mean min max ZT0-3 11.874526666666668 8.36688 14.164750000000002 ZT4-7 5.850160000000001 5.850160000000001 5.850160000000001 ZT8-11 8.869085 8.869085 8.869085 ZT12-15 16.282375000000002 13.3522 19.21255 ZT16-19 15.99365 15.99365 15.99365 ZT20-23 15.877215 15.877215 15.877215