condition mean min max ZT0-3 12.502 12.502 12.502 ZT4-7 9.24435 9.24435 9.24435 ZT8-11 8.86616 8.86616 8.86616 ZT12-15 8.333760000000002 8.333760000000002 8.333760000000002 ZT16-19 9.578783333333334 9.578783333333334 9.578783333333334 ZT20-23 11.3862 11.3862 11.3862