condition mean min max ZT0-3 6.3708100000000005 6.3708100000000005 6.3708100000000005 ZT4-7 4.926 4.926 4.926 ZT8-11 5.622685000000001 5.622685000000001 5.622685000000001 ZT12-15 8.483175 8.483175 8.483175 ZT16-19 7.828099999999999 7.828099999999999 7.828099999999999 ZT20-23 7.305899999999999 7.305899999999999 7.305899999999999