Show me the ladder when margin under 20

Ladder when margin is under 20. PTA is ranked first with a record of 7-2-0 from 9 games

#	Team	P	W	L	D	Win %	PF	PA	Home W-L	Away W-L
1	PTA	9	7	2	0	77.78	77.11	75.22	undefined-undefined	undefined-undefined
2	GWS	10	7	3	0	70.00	88.10	87.40	undefined-undefined	undefined-undefined
3	GCS	8	5	3	0	62.50	81.63	78.38	undefined-undefined	undefined-undefined
4	GEE	10	6	4	0	60.00	87.20	84.80	undefined-undefined	undefined-undefined
5	HAW	7	4	3	0	57.14	80.14	76.86	undefined-undefined	undefined-undefined
6	MEL	9	5	4	0	55.56	77.00	72.56	undefined-undefined	undefined-undefined
7	ESS	11	6	4	1	54.55	84.09	83.45	undefined-undefined	undefined-undefined
8	STK	14	7	7	0	50.00	72.50	71.50	undefined-undefined	undefined-undefined
9	BRI	8	4	3	1	50.00	85.63	84.25	undefined-undefined	undefined-undefined
10	WBD	6	3	3	0	50.00	91.17	87.17	undefined-undefined	undefined-undefined
11	COL	13	6	5	2	46.15	84.54	87.54	undefined-undefined	undefined-undefined
12	CAR	14	6	8	0	42.86	88.43	89.21	undefined-undefined	undefined-undefined
13	NTH	8	3	5	0	37.50	85.13	87.50	undefined-undefined	undefined-undefined
14	SYD	6	2	4	0	33.33	87.50	86.33	undefined-undefined	undefined-undefined
15	RIC	6	2	4	0	33.33	75.50	79.50	undefined-undefined	undefined-undefined
16	WCE	6	2	4	0	33.33	82.67	87.17	undefined-undefined	undefined-undefined
17	ADE	12	3	8	1	25.00	82.00	86.25	undefined-undefined	undefined-undefined
18	FRE	9	2	6	1	22.22	76.56	79.78	undefined-undefined	undefined-undefined