condition mean min max ZT0-3 12.1511 12.1511 12.1511 ZT4-7 9.179405 9.179405 9.179405 ZT8-11 10.5456 10.5456 10.5456 ZT12-15 12.62815 12.62815 12.62815 ZT16-19 16.98035 16.98035 16.98035 ZT20-23 13.836300000000001 13.836300000000001 13.836300000000001