condition mean min max ZT0-3 3.9497925 3.51523 4.384355 ZT4-7 4.74606 4.74606 4.74606 ZT8-11 3.6452599999999995 3.6452599999999995 3.6452599999999995 ZT12-15 0 0 0 ZT16-19 5.253825 5.253825 5.253825 ZT20-23 5.749605000000001 5.749605000000001 5.749605000000001