This one change will improve your email response rate by 15 percent

There's one thing people do that is killing their email response rates.

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Hint: It has something to do with the caps lock key.

That's the message a company called Boomerang is trying to send.

In a survey of 300,000 email subject lines (all available for public analysis), the company determined that using all caps is a sure way to get your message sent to the virtual circular bin (that is, the trash). Or...even worse. According to their research, using all caps can also get your message marked as spam. No one will ever see it.

In analyzing the subject lines, the response rate--or whether people open and read the message--dropped a full 15% compared to subject lines that use normal sentence case. It's one of the worst things you can do if you are trying to get the attention of an investor (or maybe a journalist) by email or market a new product. I've written about this before, but using creativity in a subject line is a much better strategy--one that has now worked on me countless times after writing about this recently. (You can stop now, though.)

As we all know by now, ALL CAPS is a sign of digital immaturity. It means you're yelling, for sure. It also means you don't know how to use italics or bold in apps like Slack. (Hint: You have to type asterisks like this: *bold* to use bold type.) In an email, using all caps in the subject line means you likely don't know how to craft a compelling message.

People often look for digital clues. When a message arrives that uses all caps, our brains suddenly switch into a dismissive mode. No matter what the subject line says, we assume it's a waste of time or sent from a spambot that is too dumb to use a more persuasive approach.

On social media, it's even worse. When someone types in all caps when making a comment or for a new post about their new job, we immediately assume the person is trying to get our attention without using persuasion. It's a shortcut used by people who have not been around computers long enough. I'M TRYING TO GET YOUR ATTENTION USING ALL CAPS is one of the best ways to make people ignore you.

Interestingly, email is still a viable way to market a product. I've written before about how email has become digital noise, but the reason it's still effective is that it is still incredibly public and still widely used by every age group. Anyone can send an email to anyone else. On Facebook, you can lock down your account and make it private. On Twitter, you can block people if the use a certain phrase. But, for the most part, email is an open forum. You can still block people, and apps like Gmail block spam, but if you're in marketing, there's a good chance you can get the attention of the recipient.

That is, unless you use all caps. PLEASE STOP! Thanks.

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