condition mean min max ZT0-3 6.498075 6.092835 6.903314999999999 ZT4-7 4.99329 4.99329 4.99329 ZT8-11 6.42688 6.42688 6.42688 ZT12-15 0 0 0 ZT16-19 9.661545 9.661545 9.661545 ZT20-23 7.703575000000001 7.703575000000001 7.703575000000001