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:
| Season | Episodes | Timeslot ( EST ) | Season premiere | Season finale | TV season | Rank | Viewers (in millions) |
| --- | --- | --- | --- | --- | --- | --- | --- |
| 1st | 23.0 | Tuesday 8:00PM | September 23, 2003 | May 25, 2004 | 2003–04 | 26th | 11.84 |
| 2nd | 23.0 | Tuesday 8:00PM | September 28, 2004 | May 24, 2005 | 2004–05 | 22nd | 13.57 |
| 3rd | 24.0 | Tuesday 8:00PM | September 20, 2005 | May 16, 2006 | 2005–06 | 16th | 15.27 |
| 4th | 24.0 | Tuesday 8:00PM | September 19, 2006 | May 22, 2007 | 2006–07 | 20th | 14.54 |
| 5th | 19.0 | Tuesday 8:00PM | September 25, 2007 | May 20, 2008 | 2007–08 | 14th | 14.41 |
| 6th | 25.0 | Tuesday 8:00PM | September 23, 2008 | May 19, 2009 | 2008–09 | 5th | 17.77 |
| 7th | 24.0 | Tuesday 8:00PM | September 22, 2009 | May 25, 2010 | 2009–10 | 4th | 19.33 |
| 8th | 24.0 | Tuesday 8:00PM | September 21, 2010 | May 17, 2011 | 2010–11 | 5th | 19.46 |
| 9th | 24.0 | Tuesday 8:00PM | September 20, 2011 | May 15, 2012 | 2011–12 | 3rd | 19.49 |
Question:
When was the season finale that ranked 20th?
Answer:
May 22, 2007