condition mean min max ZT0-3 17.622 17.622 17.622 ZT4-7 20.4387 20.4387 20.4387 ZT8-11 16.4236 16.4236 16.4236 ZT12-15 18.633699999999997 18.633699999999997 18.633699999999997 ZT16-19 24.31635 24.31635 24.31635 ZT20-23 17.6372 17.6372 17.6372