condition mean min max ZT0-3 4.383687500000001 4.254485 4.5128900000000005 ZT4-7 3.883355 3.883355 3.883355 ZT8-11 4.14212 4.14212 4.14212 ZT12-15 0 0 0 ZT16-19 5.132015 5.132015 5.132015 ZT20-23 5.37304 5.37304 5.37304