The Northwestern Wildcats have a point differential per game played of -7.49 all-time.

What is the average point differential per game of northwestern?

	TEAM	DIFF/GP	DIFF	GP	SEASON	W	L	T	PTS	PPG	OPP PTS	OPP PPG
1	Northwestern	-0.56	-5	9	1956	4	4	1	107	11.9	112	12.4
2	Northwestern	-23.78	-214	9	1957	0	9	0	57	6.3	271	30.1
3	Northwestern	5.67	51	9	1958	5	4	0	199	22.1	148	16.4
4	Northwestern	4.44	40	9	1959	6	3	0	174	19.3	134	14.9
5	Northwestern	0.44	4	9	1960	5	4	0	107	11.9	103	11.4
6	Northwestern	2.89	26	9	1961	4	5	0	131	14.6	105	11.7
7	Northwestern	8.78	79	9	1962	7	2	0	237	26.3	158	17.6
8	Northwestern	4.22	38	9	1963	5	4	0	162	18.0	124	13.8
9	Northwestern	-7.67	-69	9	1964	3	6	0	95	10.6	164	18.2
10	Northwestern	-6.7	-67	10	1965	4	6	0	141	14.1	208	20.8
11	Northwestern	-7.6	-76	10	1966	3	6	1	137	13.7	213	21.3
12	Northwestern	-6.4	-64	10	1967	3	7	0	149	14.9	213	21.3
13	Northwestern	-21.6	-216	10	1968	1	9	0	109	10.9	325	32.5
14	Northwestern	-16.9	-169	10	1969	3	7	0	137	13.7	306	30.6
15	Northwestern	7.2	72	10	1970	6	4	0	233	23.3	161	16.1
16	Northwestern	2.64	29	11	1971	7	4	0	212	19.3	183	16.6
17	Northwestern	-13.09	-144	11	1972	2	9	0	146	13.3	290	26.4
18	Northwestern	-10.09	-111	11	1973	4	7	0	188	17.1	299	27.2
19	Northwestern	-22.27	-245	11	1974	3	8	0	140	12.7	385	35.0
20	Northwestern	-15.36	-169	11	1975	3	8	0	149	13.5	318	28.9
21	Northwestern	-16.09	-177	11	1976	1	10	0	134	12.2	311	28.3
22	Northwestern	-21.36	-235	11	1977	1	10	0	102	9.3	337	30.6
23	Northwestern	-31.64	-348	11	1978	0	10	1	92	8.4	440	40.0
24	Northwestern	-24.64	-271	11	1979	1	10	0	115	10.5	386	35.1
25	Northwestern	-26.64	-293	11	1980	0	11	0	151	13.7	444	40.4
	Average	-7.49	-69.8	9.3		3.6	5.6	0.1	178.6	19.2	248.3	26.7
	Total	-7.49	-5,861	782		305	471	6	15,000	19.2	20,861	26.7