condition mean min max ZT0-3 7.20755 7.20755 7.20755 ZT4-7 6.8893450000000005 6.8893450000000005 6.8893450000000005 ZT8-11 10.89495 10.89495 10.89495 ZT12-15 13.7886 13.7886 13.7886 ZT16-19 14.74595 14.74595 14.74595 ZT20-23 9.43398 9.43398 9.43398