condition mean min max ZT0-3 7.8597624999999995 6.980725 8.7388 ZT4-7 6.28656 6.28656 6.28656 ZT8-11 3.723095 3.723095 3.723095 ZT12-15 0 0 0 ZT16-19 5.1074850000000005 5.1074850000000005 5.1074850000000005 ZT20-23 6.841225 6.841225 6.841225