Presenting statistical information is essential to any business during meetings with clients or colleagues. Pie charts have long been a tool employed to provide an easily understood visual breakdown of information. Businessdictionary.com defines pie charts as a visual circular graph used to show the relative sizes of differing components of a set of data for measurement and comparison.
Pie charts provide the advantage of functioning as a visual aid to help your audience examine and interpret the data you present. Data is often difficult to understand when presented as a series of black-and-white statistics and calculations. A pie chart creates a visual model, which people can use when comparing different data sets. Using different colours, pie charts divide information into sections resembling pie slices. Each "slice" is usually accompanied by a percentage number, and its size changes accordingly.
Pie charts use percentages to illustrate quantities. This is a clear advantage when presenting statistics such as those for profits and expenses. The effectiveness of pie charts for examining percentages lies in audience members immediately understanding what you intend to communicate. The simple presentation of data makes it accessible to audiences of all ages and education levels.
Disadvantage: not exact
Since pie charts use percentages to illustrate numerical values, specific figures are not provided. The graph provides a simple overview of a data set in an easy-to-read format, but does not provide precise information or leave room for other data sets. Pie charts are sometimes too simplistic when you are trying to convey more complex concepts or data sets. Pie charts can easily be manipulated to present false information, which limits their use in situations which require accuracy and precision.
Disadvantage: Can't compare 2 data sets
Pie charts are capable of visually displaying only one set of data. Individuals who need to display and compare multiple sets of data need to find another type of graph for their presentation. This limits the use of pie charts in more statistically intense/demanding presentations.