condition mean min max ZT0-3 621.095307 621.095307 621.095307 ZT4-7 649.4500395 649.4500395 649.4500395 ZT8-11 707.693595 707.693595 707.693595 ZT12-15 722.4673155 722.4673155 722.4673155 ZT16-19 752.5156555 752.5156555 752.5156555 ZT20-23 669.3453615 669.3453615 669.3453615