Bar graphs are used to show frequency or
totals of data. Sometimes there is just one data set like this one showing the value of New Zealand’s total agricultural seafood and forestry exports in 2011. Other times bar graphs are used to show the totals of different data sets. In this case I have some data on the numbers of men and woman participating in selected sports in New Zealand. Now I will use this data to show you how to draw a comparative bar graph. First draw the x and y axis. Starting with 0 label the y axes to
whatever figure is the highest. Make sure you scale units in even multiples of fives, tens or twenties so you have a consistent scale when labeling. Do not go 0, 13, 27,
53, 129 or anything like that. Multiple bar graphs require a key, also
known as a legend. I will use blue for males and pink for females. On the x-axis we will draw our bars. Make sure your bars are accurate. Your bars must have gaps between them. Otherwise you are drawing a histogram
rather than a bar graph Also make sure your bars have the same
width. On histograms the bars are joined together. Bar graphs have gaps. Give your graph an appropriate title. Here is our completed graph.