<P> The following is a table for the seasonal rankings based on average total estimated viewers per episode of The Vampire Diaries . "Rank" refers to how The Vampire Diaries rated compared to the other television series which aired during prime time hours . </P> <Table> <Tr> <Th> Season </Th> <Th> Timeslot (ET) </Th> <Th> Episodes </Th> <Th_colspan="2"> First aired </Th> <Th_colspan="2"> Last aired </Th> <Th> TV season </Th> <Th> Rank </Th> <Th> Avg . viewers (millions) </Th> </Tr> <Tr> <Th> Date </Th> <Th> Viewers (millions) </Th> <Th> Date </Th> <Th> Viewers (millions) </Th> </Tr> <Tr> <Td> </Td> <Td> Thursday 8: 00 pm </Td> <Td> 22 </Td> <Td> September 10, 2009 </Td> <Td> 4.91 </Td> <Td> May 13, 2010 </Td> <Td> 3.47 </Td> <Td> 2009--10 </Td> <Td> 118 </Td> <Td> 3.60 </Td> </Tr> <Tr> <Td> </Td> <Td> 22 </Td> <Td> September 9, 2010 </Td> <Td> 3.36 </Td> <Td> May 12, 2011 </Td> <Td> 2.86 </Td> <Td> 2010--11 </Td> <Td> 193 </Td> <Td> 3.17 </Td> </Tr> <Tr> <Td> </Td> <Td> 22 </Td> <Td> September 15, 2011 </Td> <Td> 3.10 </Td> <Td> May 10, 2012 </Td> <Td> 2.53 </Td> <Td> 2011--12 </Td> <Td> 166 </Td> <Td> 2.91 </Td> </Tr> <Tr> <Td> </Td> <Td> 23 </Td> <Td> October 11, 2012 </Td> <Td> 3.18 </Td> <Td> May 16, 2013 </Td> <Td> 2.24 </Td> <Td> 2012--13 </Td> <Td> 133 </Td> <Td> 2.97 </Td> </Tr> <Tr> <Td> 5 </Td> <Td> 22 </Td> <Td> October 3, 2013 </Td> <Td> 2.59 </Td> <Td> May 15, 2014 </Td> <Td> 1.61 </Td> <Td> 2013--14 </Td> <Td> 147 </Td> <Td> 2.68 </Td> </Tr> <Tr> <Td> 6 </Td> <Td> 22 </Td> <Td> October 2, 2014 </Td> <Td> 1.81 </Td> <Td> May 14, 2015 </Td> <Td> 1.44 </Td> <Td> 2014--15 </Td> <Td> 160 </Td> <Td> 1.54 </Td> </Tr> <Tr> <Td> 7 </Td> <Td> Thursday 8: 00 pm (1--9) Friday 8: 00 pm (10--22) </Td> <Td> 22 </Td> <Td> October 8, 2015 </Td> <Td> 1.38 </Td> <Td> May 13, 2016 </Td> <Td> 1.04 </Td> <Td> 2015--16 </Td> <Td> 141 </Td> <Td> 1.95 </Td> </Tr> <Tr> <Td> 8 </Td> <Td> Friday 8: 00 pm </Td> <Td> 16 </Td> <Td> October 21, 2016 </Td> <Td> 0.98 </Td> <Td> March 10, 2017 </Td> <Td> 1.15 </Td> <Td> 2016--17 </Td> <Td> 140 </Td> <Td> 1.71 </Td> </Tr> </Table> <Tr> <Th> Season </Th> <Th> Timeslot (ET) </Th> <Th> Episodes </Th> <Th_colspan="2"> First aired </Th> <Th_colspan="2"> Last aired </Th> <Th> TV season </Th> <Th> Rank </Th> <Th> Avg . viewers (millions) </Th> </Tr> <Tr> <Th> Date </Th> <Th> Viewers (millions) </Th> <Th> Date </Th> <Th> Viewers (millions) </Th> </Tr>

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