condition mean min max ZT0-3 12.786689 12.786689 12.786689 ZT4-7 14.319019 14.319019 14.319019 ZT8-11 19.722051 19.722051 19.722051 ZT12-15 25.289031 25.289031 25.289031 ZT16-19 17.602612 17.602612 17.602612 ZT20-23 13.480426 13.480426 13.480426