For example, a series drop area is not displayed for a pie chart because pie charts consist of only one series.
1	For	for	ADV	_	Case=Nom	10	advmod	_	_
2	example	example	NOUN	_	Number=Sing	1	fixed	_	SpaceAfter=No
3	,	,	PUNCT	Comma	_	1	punct	_	_
4	a	a	DET	IND-SG	Definite=Ind|PronType=Art	7	det	_	_
5	series	series	NOUN	SG-NOM	Number=Sing	7	compound	_	_
6	drop	drop	NOUN	SG-NOM	Number=Sing	7	compound	_	_
7	area	area	NOUN	SG-NOM	Number=Sing	10	nsubj:pass	_	_
8	is	be	AUX	PRES-AUX	Mood=Ind|Number=Sing|Person=3|Tense=Pres|VerbForm=Fin	10	aux:pass	_	_
9	not	not	PART	NEG	_	10	advmod	_	_
10	displayed	display	VERB	PASS	Tense=Past|VerbForm=Part|Voice=Pass	0	root	_	_
11	for	for	ADP	_	_	14	case	_	_
12	a	a	DET	IND-SG	Definite=Ind|PronType=Art	14	det	_	_
13	pie	pie	NOUN	SG-NOM	Number=Sing	14	compound	_	_
14	chart	chart	NOUN	SG-NOM	Number=Sing	10	obl	_	_
15	because	because	SCONJ	_	_	18	mark	_	_
16	pie	pie	NOUN	SG-NOM	Number=Sing	17	compound	_	_
17	charts	chart	NOUN	PL-NOM	Number=Plur	18	nsubj	_	_
18	consist	consist	VERB	PRES	Mood=Ind|Tense=Pres|VerbForm=Fin	10	advcl	_	_
19	of	of	ADP	_	_	22	case	_	_
20	only	only	ADV	_	_	21	advmod	_	_
21	one	one	NUM	CARD-SG	NumType=Card	22	nummod	_	_
22	series	series	NOUN	SG-NOM	Number=Sing	18	obl	_	SpaceAfter=No
23	.	.	PUNCT	Period	_	10	punct	_	_
