Rounding

Rounding numbers can make them easier to read and compare, although this must be balanced against the loss of precision.

The level of rounding you use (for example, one decimal place or two significant figures) should be effective, and chosen according to the intended use. Always use the lowest level possible for the intended user.

It should also be consistent throughout your piece of writing.

For the “inquiring citizen”, that is, a broader, less statistical audience:

For the “information forager”, for example, a local politician making decisions about future council tax charges:

For the “expert analyst”, for example, in a statistical journal discussing the detailed methodology behind the estimation, or in a situation where reproducibility is important:

Effective rounding

Effective rounding can be used to communicate and present numbers so that they can be understood quickly and easily. Remove any unimportant or irrelevant information, but keep the detail in the data.

Look at whether there is a difference between the first numbers, second numbers, third numbers and so on. You should round the numbers for comparison to two effective digits.

When using effective rounding you may need an extra level of rounding when a value is small enough that the detail is removed when using two effective digits. If the value is not important it could be removed from the table. If it is important the level of effective rounding should be adjusted to an appropriate level.