condition mean min max ZT0-3 3.3584875 2.849535 3.86744 ZT4-7 3.9017850000000003 3.9017850000000003 3.9017850000000003 ZT8-11 9.65896 9.65896 9.65896 ZT12-15 0 0 0 ZT16-19 10.453005000000001 10.453005000000001 10.453005000000001 ZT20-23 7.65238 7.65238 7.65238