condition mean min max ZT0-3 4.383745 3.74128 5.026210000000001 ZT4-7 4.28149 4.28149 4.28149 ZT8-11 6.18462 6.18462 6.18462 ZT12-15 0 0 0 ZT16-19 7.048415 7.048415 7.048415 ZT20-23 5.498085 5.498085 5.498085