Definitions of e-mail spam, or junk e-mail, typically include the idea that the e-mail is unsolicited and sent in bulk. Beginning in the early 1990s the amount of email spam grew steadily until recently, with a total volume of over 100 billion e-mails per day in April 2008. The amount being received has begun to decrease due to the use of better filtering software. As unbelievable as it might be, fewer than 200 spammers send about 80% of all spam. The chart below lists the percentage of e-mail spam relayed by each country in 2007.
Country Percentage
Brazil........... 4.1
China .......... 8.4
EU ........... 17.9
France ......... 3.3
Germany ........ 4.2
India ........... 2.5
Italy ........... 2.8
Poland ......... 4.8
Russia .......... 3.1
S Korea ........ 6.5
Turkey ......... 2.9
UK ........... 2.8
US ........... 19.6
a. Construct a bar graph of this information with the percentages in declining order.
b. Explain why a Pareto diagram of this information cannot be constructed.