（When calculating the Q value, how far below the decimal point should we do the calculation?）**Q.**

When calculating the Q value how far below the decimal point should we do the calculation. Some say 3 digits below the decimal point is good enough. Please guide us with the correct interpretation. (30 Nov 17)

When calculating the Q value how far below the decimal point should we do the calculation. Some say 3 digits below the decimal point is good enough. Please guide us with the correct interpretation. (30 Nov 17)

**A.**

The Q value must not exceed 1.0 and must be rounded up to the first decimal place. This means 1.0000001 for instance would truncate to 1.1 and therefore exceeds 1.0. There is no fixed rule on how far below the decimal point you should go. . You need simply to ensure that the Q value would not exceed 1.0.