condition mean min max ZT0-3 14.412933333333335 13.421700000000001 15.257100000000001 ZT4-7 9.771165 9.771165 9.771165 ZT8-11 8.691155 8.691155 8.691155 ZT12-15 11.0683 10.34515 11.791450000000001 ZT16-19 10.133054999999999 10.133054999999999 10.133054999999999 ZT20-23 12.4361 12.4361 12.4361