Scale: the small aspect that can make or break the effectiveness of your graph
            Just as there are many types of graphs, there are also many aspects of graphs.   Bar graphs in particular can be very effective when used with the right tools but very ineffective when not. One of these tools is scale.  Scale is a simple aspect of graphing data and information that can either skew the data or highlight an aspect of the data.

Often when displaying information via a bar graph the goal can be to do one of two things; to highlight a change in the amount of something over time, or to the differences in current statuses of different categories.  In the case the right, the goal is to highlight the change in heath expenditure in Finland from 200 to 2009.

The point if displaying this information by graph was to show that the amount of US dollars that Fins spent on health care per year was steady until 2002 when it took a drastic incline and continued to incline until 2009.  By using a scale from $0 to $30000 on the top graph, this change in expenditure is hardly visible, since the maximum money spent is just over $8000.  However by changing the scale to $0 to $8000 in the bottom graph readers are able to accurately see the rapid incline in the height of the bars and therefore the rapid incline in Finish health expenditure.

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