ER (TV series) Ratings Ratings

| Season | Season_premiere | Season_finale | TV_season | Viewer_rank_ | Households_Viewers_in_millions |
|---|---|---|---|---|---|
| 11 | September 23, 2004 | May 19, 2005 | 2004–2005 | #16 | 15.17 |
| 12 | September 22, 2005 | May 18, 2006 | 2005–2006 | #30 | 12.06 |
| 13 | September 21, 2006 | May 17, 2007 | 2006–2007 | #40 | 11.56 |
| 14 | September 27, 2007 | May 15, 2008 | 2007–2008 | #54 | 9.20 |
| 15 | September 25, 2008 | April 2, 2009 | 2008–2009 | #37 | 10.30 |