Figures
Write numbers one to nine as words, 10 and above as digits. When writing a range, just use digits. ‘First’ to ‘ninth’ are also words, but 10th and above are written as digits, without superscript.
Percentages
Percentages are an exception. Use the digits, even if it’s below 10. And use the % symbol.
Fractions
Write fractions as words and hyphenate them, eg ‘A shareholder with a two-thirds majority voted against the proposal’.
But don’t do this in titles as it takes up too much space, eg ‘2/3 of shareholders vote against proposal’.
Headings
Headings and titles are another exception. Use the digits.
Millions/Billions
We tend to use the written word ‘million’, unless it’s for currencies, quantities, measurements and inanimate objects, in which case, we use ‘m’. The same rules apply to billion and trillion, which are written as bn and tn. (See currencies section for guidance.)