The bad debt ratio for a financial institution is defined to be the dollar value of loans defaulted divided by the total dollar value of all loans made. Suppose that a random sample of sixty-five banks in Illinois is selected and that their bad debt ratios (recorded as a percentage) are presented in this file:

bank	Bad Debt Ratio
1	3.38
2	5.15
3	4.63
4	9.69
5	8.32
6	3.58
7	5.9
8	7.33
9	6.28
10	6.87
11	3.93
12	5.76
13	3.98
14	3.66
15	7.46
16	5.59
17	6.39
18	6.49
19	2.31
20	7.84
21	9.2
22	4.64
23	5.38
24	4.23
25	7.12
26	3.48
27	2.87
28	4.59
29	7.43
30	8.34
31	5.15
32	5.84
33	4.95
34	5.6
35	7.52
36	5.23
37	7.88
38	8.86
39	4.42
40	6.64
41	9.25
42	6.53
43	5.35
44	6.04
45	5.19
46	2.87
47	2.91
48	1.77
49	2.34
50	4.22
51	3.2
52	3.14
53	2.86
54	4.05
55	2.01
56	3.42
57	4.38
58	3.1
59	1.76
60	3.16
61	4.06
62	4.21
63	2.16
64	2.76
65	2.46

Banking officials claim that the mean bad debt ratio for all Midwestern banks is 3.5 percent and that the mean bad debt ratio for Illinois banks is higher.

What is t-value?