condition mean min max ZT0-3 6.5437175 6.254284999999999 6.83315 ZT4-7 4.441319999999999 4.441319999999999 4.441319999999999 ZT8-11 5.5375049999999995 5.5375049999999995 5.5375049999999995 ZT12-15 0 0 0 ZT16-19 8.371725000000001 8.371725000000001 8.371725000000001 ZT20-23 8.412700000000001 8.412700000000001 8.412700000000001