Hansard Style Manual .au

Spell out million, billion and trillion when used with amounts of money. The abbreviation m ($200m) should not be used. $200 million: $2 billion. $4 trillion. In other cases, follow the general rules applying to numbers (see section 9.1.1 One to nine): express numbers one to nine—however used in larger numerical compounds—in words and numbers above nine in figures. For example: NUMBER ... ................
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