condition mean min max ZT0-3 14.080476666666668 7.81898 17.65245 ZT4-7 7.913895 7.913895 7.913895 ZT8-11 7.634715 7.634715 7.634715 ZT12-15 10.050615 9.29323 10.808 ZT16-19 12.13275 12.13275 12.13275 ZT20-23 18.5333 18.5333 18.5333