75% of emails are spam
More than seventy-five percent of all emails sent are considered spam and are not opened. The first spam email was sent in 1978, but the definition of the word ‘spam’ as an undesirable message didn’t appear in dictionaries until about 1998. About 183 billion spam emails are sent every day.
Bonus fact: The word ‘spam’ originated from a Monty Python sketch where everything on the menu has spam in it.
Source:
True or False by Andrea Mills, Dorling Kindersley