Choosing Graph and Chart types

Using Charts and

Graphs

Types of Graphs

Types

� Bar/Column

� Line

� Pie

� Scatter

Why

� Trends

� Comparisons

� Quicker/Easier to understand

Column or Bar

“Discrete” Data

No half values on the category axis

0

10

20

30

40

Unit 1 Unit 2 Unit 3 Unit 4 0 20 40

Unit 1

Unit 2

Unit 3

Unit 4

Line

0

20

40

60

2005 2006 2007 2008 2009 2010

Staff Turnover

0

20

40

60

80

Jan Feb March April

Sales

Tesco

Asda

Continuous data

Often with time on X axis

Trends

PieFavourite Sports

Rugby

Football

Tennis

Cricket

Percentage and Proportion

Only for full data sets

Girls

Boys

Class Gender Distribution

Scatter

Experimental Results

Looking for trends or correlation

“Trend line” or

“Line of best fit”

0

5

10

15

20

0 2 4 6 8 100

5

10

0 2 4 6 8 10

Look out for…

0

50

100

Skewed range

Compressed scale

Incorrect range in Excel – e.g. including the total row

Choose Start Point

0

100

90

100

www.statswales.wales.gov.uk

www.statistics.gov.uk

www.informationisbeautiful.net

www.coolinfographics.com

Sources for statistics