condition mean min max ZT0-3 6.81673 6.81673 6.81673 ZT4-7 5.012215 5.012215 5.012215 ZT8-11 4.819285 4.819285 4.819285 ZT12-15 2.3972499999999997 2.3972499999999997 2.3972499999999997 ZT16-19 5.22424 5.22424 5.22424 ZT20-23 8.378910000000001 8.378910000000001 8.378910000000001