condition mean min max ZT0-3 19.970827 19.970827 19.970827 ZT4-7 20.8149425 20.8149425 20.8149425 ZT8-11 24.300804 24.300804 24.300804 ZT12-15 19.505753 19.505753 19.505753 ZT16-19 20.4684125 20.4684125 20.4684125 ZT20-23 20.859353499999997 20.859353499999997 20.859353499999997