condition mean min max ZT0-3 4.44862 4.44862 4.44862 ZT4-7 3.34902 3.34902 3.34902 ZT8-11 2.856025 2.856025 2.856025 ZT12-15 5.940735 5.940735 5.940735 ZT16-19 6.2509950000000005 6.2509950000000005 6.2509950000000005 ZT20-23 6.03904 6.03904 6.03904