That's useful research information for Mozilla when planning its next browser release. But if these are users on our Web site, clicking the Back button is bad news for us!
In fact, if you're paying for Google advertising, Google penalises you (that is, charges you more for your ads) if too many users click the Back button after visiting your site.
So what should you aim for instead?
What you want on your Web site is for users to click the "forward" button instead of the Back button.
There actually isn't a "forward" button on most Web pages. My point is, always aim to take your site visitors forward on their journey through your Web site.
What does this mean in practice?
When somebody visits any page on your site - whether it's the home page or an internal page, whether they know you or not, whether they've visited the site before or not - they are asking themselves three questions:
1. Is this relevant for me?
If your site visitor can't tell easily whether this page applies to them, they'll leave. That might be OK if they weren't the target market for that page; but it's a disaster if they were your target market.
The key here is to know what target market you're identifying (and the narrower your niche the better), then make sure everything you write clearly demonstrates you're writing for that market.
2. Assuming it is relevant, is it useful for me?
Do you know what problems you're solving for your site visitors? What's keeping them up at night, is a niggling question at the back of their mind, or consumes their thoughts throughout the day?
Make sure you know the problems, know what you're offering as a solution and know what makes your solution different. Then make sure everything on your Web site supports this.
3. What do I do next?
Too many Web pages end without any call to action. Don't be afraid to ask them for action - whether it's to pick up the phone, send you an e-mail, register for a newsletter, or pull out their credit card and hand over money to you.
If you've done a good job with the first two questions, your site visitor wants to take action. Don't leave it to chance - tell them what you want them to do!
How does your Web site measure up?
You must answer all three questions, or they'll click the Back button - possibly never to return.
Look at your Web site with a critical eye, and check whether your ideal site visitor will be able to answer all three questions - clearly and easily.
This is not only about the home page. It's about every page on the path you've planned out for each type of site visitor.