It’s getting cold outside. Thanksgiving is just a few weeks way and I’m excited to see my family and enjoy an amazing feast. While some others will be carelessly eating away at their pumpkin pie, I’ll be analyzing the size of each slice to determine the varying ratios. Did I just get the smallest slice because of my age? How did Grandpa get the largest slice?
If the internet is true, pie charts have been around for over 200 years. Yet here we are, coming up on 2012 and there’s still controversy over the use of pie charts. Ratio charts, like the pie chart, take all of the contributing measures and compares them as a proportion. Summing each proportion will equal 100%. For example, if I eat the whole pie, I get the whole 100%. If I equally share the pie with my wife, I get to have 50%. In a few weeks I’m estimating a slice of pie that is 11% of the whole pie. I don’t care if I get 20 ounces of pie but I definitely want a fair proportion. That’s where the controversy exists.
Some analysts want to eliminate pie charts in exchange for bar charts. Bar/Column charts can show similar visual data, but will not contain proportions. With a bar chart, I can still visualize my slice of pie as being the smallest, but I can’t tell if we finished the whole pie! Examine the images below and determine for yourself. Skepticism will continue for another 200 years on if or when it’s okay to use a pie chart.
Ken Rose– Technical Consultant, iDashboards