Most people don't understand numbers above a billion, and many people don't even know what a billion represents.
There's also an internationalization issue here: "billion" represents a thousand millions in American English, but a million millions in many European languages.
The average reader does not know how to properly evaluate and interpret the statistics he or she reads.
The main reason behind the poor use of statistics is a lack of understanding about what statistics can and cannot do.
In many ways, this problem is quite similar to that experienced with direct quotes.
Too often, quotes are expected to do all the work and are treated as part of the argument, rather than a piece of evidence requiring interpretation (see our handout on how to quote.) But if you leave the interpretation up to the reader, who knows what sort of off-the-wall interpretations may result?On the other hand, it's better to use numerals when stating the exact number (e.g., "we have tested 2,692 users").Disclosing the exact number also increases the statement's credibility.—Mark Twain The purpose of this handout is to help you use statistics to make your argument as effectively as possible. Apparently freed of all the squishiness and ambiguity of words, numbers and statistics are powerful pieces of evidence that can effectively strengthen any argument. As simple and straightforward as these little numbers promise to be, statistics, if not used carefully, can create more problems than they solve.Many writers lack a firm grasp of the statistics they are using.For specific facts, representing numbers using digits rather than letters increases usability for people who are looking for either a particular piece of information or the gist of a page.This often includes e-commerce shoppers and very often includes customers visiting B2B sites, whether they're shopping or just doing research.We've known the basic guidelines for writing for the Web since our earliest studies in 1997.A key finding is that most website users don't read all your words.Even when users aren't scanning for data, having your facts stand out visually by presenting them as numerals is an easy way to enhance credibility by making your page seem more useful.Full eyetracking report on how users read on the web is available for download.