No commas

e.g. "1000" instead of "1,000"

No units of measurement

Units should be in metadata instead

Express as full number where possible

e.g. "1200000" instead of "1.2" (million)

If rounded, indicate in metadata

No rounding if possible

Give raw numbers as far as possible

If rounding is needed, try to provide at least 2 decimal places of precision and indicate rounding in metadata

Percentages can be expressed as either a proportion out of 1 or 100.

e.g. 20% can be expressed as 20 or 0.2

The representation of percentages must be consistent throughout your dataset (e.g. among different percentage fields)

You must indicate how percentages are expressed in the data dictionary