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 | Air Date | Timeslot (EST) | Season | Rating | Share | 18–49 | Viewers (m) | Rank (#) |
| --- | --- | --- | --- | --- | --- | --- | --- | --- |
| " I Knew You When " | October 1, 2008 | Fri. 9:00PM | 2009.0 | 2.8 | 5.0 | 1.6 | 4.54 | N/A |
| " Tami Knows Best " | October 8, 2008 | Fri. 9:00PM | 2009.0 | 2.5 | 4.0 | 1.4 | 3.96 | N/A |
| " How the Other Half Live " | October 15, 2008 | Fri. 9:00PM | 2009.0 | 2.5 | 4.0 | 1.4 | 4.0 | N/A |
| " Hello, Goodbye " | October 22, 2008 | Fri. 9:00PM | 2009.0 | 2.5 | 4.0 | 1.4 | 4.21 | N/A |
| " Every Rose Has Its Thorn " | October 29, 2008 | Fri. 9:00PM | 2009.0 | 2.2 | 4.0 | 1.1 | 3.46 | N/A |
| " It Ain't Easy Being J.D. McCoy " | November 5, 2008 | Fri. 9:00PM | 2009.0 | 2.5 | 4.0 | 1.4 | 3.93 | N/A |
| " Keeping Up Appearances " | November 12, 2008 | Fri. 9:00PM | 2009.0 | 2.6 | 5.0 | 1.5 | 4.22 | N/A |
| " New York, New York " | November 19, 2008 | Fri. 9:00PM | 2009.0 | 2.3 | 4.0 | 1.2 | 3.8 | N/A |
| " Game of the Week " | December 3, 2008 | Fri. 9:00PM | 2009.0 | 2.7 | 5.0 | 1.5 | 4.4 | N/A |
| " The Giving Tree " | December 10, 2008 | Fri. 9:00PM | 2009.0 | 2.5 | 4.0 | 1.2 | 3.84 | N/A |
| " A Hard Rain's Gonna Fall " | December 17, 2008 | Fri. 9:00PM | 2009.0 | 2.5 | 4.0 | 1.2 | 3.95 | N/A |
| " Underdogs " | January 7, 2009 | Fri. 9:00PM | 2009.0 | 2.3 | 4.0 | 1.2 | 3.61 | N/A |
| " Tomorrow Blues " | January 14, 2009 | Fri. 9:00PM | 2009.0 | 2.6 | 5.0 | 1.3 | 4.36 | N/A |
Question:
What is the total number of ratings among the 18 to 49 group that was aired on January 7, 2009?
Answer:
1.0