What kind of graphs are good when you want to compare amounts?

Answer 1

The answer depends on how many variables you wish to compare and whether of not the variables are related.

For example, if you have measurements of height and weight for a group of people, AND the two variables are tied, then a scatter graph is probably best. But if you cannot tie a height measurement to a weight measurement, then a clustered (or grouped) bar graph using two vertical axes is appropriate.

With more than 2 variables, you may wish to consider three-dimensional scatter plots or bar charts.

If you want to compare the amounts, as parts of a whole, concentric pie charts many be best. For example, two pies in which the inner pie represents a company's expenditure - with each slice representing inputs - and the outer pie representing revenues - with each slice representing outputs. The difference between the areas of the two pies could represent the profits.

Answer 2

I would say bar graphs.