Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| Episode Number | Episode | Rating | Share | Rating/Share (18-49) | Viewers (millions) | Rank (Timeslot) | Rank (Overall) |
| --- | --- | --- | --- | --- | --- | --- | --- |
| 1.0 | "Pilot" | 4.8 | 8.0 | 2.3/6 | 7.56 | TBA | #35 |
| 2.0 | "Live and Let Spy" | 3.8 | 6.0 | 1.8/5 | 6.22 | 3 | 47 |
| 3.0 | "The Great Right Hope" | 4.1 | 7.0 | 1.8/5 | 6.59 | 3 | 45 |
| 4.0 | "The Tommy Brown Affair" | 3.8 | 6.0 | 1.8/5 | 6.16 | 3 | 45 |
| 5.0 | "Shipping Out" | 3.5 | 6.0 | 1.7/5 | 5.14 | TBA | 59 |
| 6.0 | "Left of the Dial" | 3.6 | 6.0 | 1.4/4 | 5.50 | 4 | 54 |
Question:
What is overall rank when viewers are at 6.59 million?
Answer:
45.0