condition mean min max ZT0-3 7.8292399999999995 7.8292399999999995 7.8292399999999995 ZT4-7 4.739725 4.739725 4.739725 ZT8-11 0.8940425000000001 0.8940425000000001 0.8940425000000001 ZT12-15 0.7447265000000001 0.7447265000000001 0.7447265000000001 ZT16-19 2.6680200000000003 2.6680200000000003 2.6680200000000003 ZT20-23 12.99405 12.99405 12.99405