Line graph

What is it?

Line graphs are a common way of presenting data in the form of a picture.
They show the direct relationship, for example, between two quantities at a glance


When to use it

  • Gathering data
  • Analysing data
  • Planning and implementing solutions
  • implementing and testing solutions
  • Ensuring continuous improvement

What does it achieve?

In the problem solving process, it is often easier to see results when they are displayed on a graph than if the results were presented in the form of a table.

Seeing how variables have changed in the past can give a useful guide as to what can be expected in the future.


  • Time series graphs are used to show relationships between a variable and time
  • An index chart can be used to show percentage comparisons
  • A frequency polygon is used to show frequency distributions
  • An Ogive is used to show cumulative frequency distribution
  • A conversion chart can be used to display the relationship between two variables