Grouping/Categorizing labels in charts

[Tong Sun]

Hi, 

Is it possible to group the labels in google charts into different categories?

See the following example, from Ms Excel Pivot Chart:

In above charts, above each label, there is another level, containing two groups, "Compact" & "MidSize". Can google charts do that as well? 

Working example appreciated, you can use the following table if you like. 

	Sex	female	male
Pclass	Age
class1	(0, 18]	0.909091	0.800000
	(18, 81]	0.972973	0.375000
class2	(0, 18]	1.000000	0.600000
	(18, 81]	0.900000	0.071429
class3	(0, 18]	0.511628	0.215686
	(18, 81]	0.423729	0.133663

Thanks