A bar graph (also known as a bar chart) is a diagram that uses proportional-width bars to compare data among categories. A bar graph may run horizontally or vertically. The important thing to know is that the longer the bar, the greater its value.
Bar graphs display data in a way that is similar to line graphs. Line graphs are useful for displaying smaller changes in a trend over time. Bar graphs are better for comparing larger changes or differences in data among groups.
Bar graphs have three key attributes.
- It's easy to compare sets of data between different groups at a glance.
- The relationship of the data between the x and y axes is easy to see.
- They are effective in presenting trends or changes over time.
Bar graphs consist of two axes. On a vertical bar graph, as shown above, the horizontal axis (or x-axis) shows the data categories. In this example, they are years. The vertical axis (or y-axis) is the scale. The colored bars are the data series.
When to Use a Bar Graph
Bar graphs are an effective way to compare items between different groups. This bar graph shows a comparison of numbers on a quarterly basis over a four-year period of time. Users of this chart can compare the data by quarter on a year-over-year trend, and also see how the annual sales are distributed throughout each year.
Bar graphs are an extremely effective visual to use in presentations and reports. They are popular because they allow the reader to recognize patterns or trends far more easily than looking at a table of numerical data.
Types of Bar Graphs
When presenting data visually, there are several different styles of bar graphs to consider.
Vertical Bar Graph
The most common type of bar graph is the vertical bar graph. It is very useful when presenting a series of data over time. The vertical bar chart below shows a series of quarterly data, categorized by year. The reader can easily see not only the trends of sales over the four-year period, but also how the sales compare during each quarter.
One disadvantage of vertical bar graphs is that they don't leave much room at the bottom of the chart if long labels are required.
Horizontal Bar Graph
Converting the vertical data to a horizontal bar chart solves this problem. There is plenty of room for the long label along the vertical axis, as shown below.
Stacked Bar Graph
The stacked bar graph is a visual that can convey a lot of information. Look at the stacked bar graph below, and you can see that there are eight data series (world regions) within each category (year).
Trying to show all of these data series in a standard bar chart would be impractical. The stacked bar chart in this example allows us to pick out three important facts:
- The total population is increasing dramatically over the time period displayed.
- The largest region is the purple segment—Non-OECD Asia—which is also increasing very rapidly.
- Africa, represented by the gold band second from the top, is clearly the second-largest region and has a rapidly growing population.
One of the disadvantages of a stacked bar chart is that may not show data in as clear a manner as intended, and if not read carefully, might even be misleading. For example, in the above chart, the population of Africa increased more than 100% during this time period while the population of Non-OECD Asia increased by about 50%. Perhaps lost in this chart is that the population of the Middle East also grows by more than 100%.
The point is to make sure that you select the type of graph that best presents the data you want to emphasize.
How to Create a Bar Chart with SmartDraw
Watch this five-minute video for a quick training lesson on creating charts and graphs in SmartDraw.
Here are some key features of SmartDraw that make it fast and easy to create bar charts.
Express Bar Charts
Create charts and graphs without having to make a spreadsheet first. Simply pick a chart and type your data directly into the bars. You can even drag the bars to represent the right values.
3D Bar Charts
Dazzle your audience with SmartDraw 3D bar charts and area charts. Use the gallery interface to change the appearance with one click.
Microsoft Excel® Integration
Import the data for your chart directly from Excel®. Simply browse to your file, and then select which rows and columns you want to chart. SmartDraw imports the data and builds your chart automatically.
Bar Graph Templates
SmartDraw includes a specialized template for every type of chart to help you get started right away.
Bar Graph Examples
In addition to the quick-start templates, SmartDraw includes dozens of completed chart examples for every type of chart. Open one that is most similar to your project, and easily edit the data by either importing from Excel® or simply dragging the bars, lines, or pie slices.