<Table> Capitals--Penguins rivalry <Tr> <Td_colspan="2"> Washington Capitals Pittsburgh Penguins </Td> </Tr> <Tr> <Th> First meeting </Th> <Td> November 16, 1974 </Td> </Tr> <Tr> <Th> Latest meeting </Th> <Td> May 7, 2018 </Td> </Tr> <Tr> <Th> Next meeting </Th> <Td> TBA </Td> </Tr> <Tr> <Th_colspan="2"> Statistics </Th> </Tr> <Tr> <Th> Meetings total </Th> <Td> 290 </Td> </Tr> <Tr> <Th> All - time series </Th> <Td> 148--125--16 (PIT) </Td> </Tr> <Tr> <Th> Regular season series </Th> <Td> 108--97--16 (PIT) </Td> </Tr> <Tr> <Th> Postseason results </Th> <Td> 40--28 (PIT) </Td> </Tr> <Tr> <Th> Longest win streak </Th> <Td> WSH W9 </Td> </Tr> <Tr> <Th> Current win streak </Th> <Td> WSH W2 </Td> </Tr> <Tr> <Th_colspan="2"> Post-season history </Th> </Tr> <Tr> <Td_colspan="2"> <Ul> <Li> 1991 Patrick Division Finals: Penguins won, 4--1 </Li> <Li> 1992 Patrick Division Semifinals: Penguins won, 4--3 </Li> <Li> 1994 Eastern Conference Quarterfinals: Capitals won, 4--2 </Li> <Li> 1995 Eastern Conference Quarterfinals: Penguins won, 4--3 </Li> <Li> 1996 Eastern Conference Quarterfinals: Penguins won, 4--2 </Li> <Li> 2000 Eastern Conference Quarterfinals: Penguins won, 4--1 </Li> <Li> 2001 Eastern Conference Quarterfinals: Penguins won, 4--2 </Li> <Li> 2009 Eastern Conference Semifinals: Penguins won, 4--3 </Li> <Li> 2016 Eastern Conference Second Round: Penguins won, 4--2 </Li> <Li> 2017 Eastern Conference Second Round: Penguins won, 4--3 </Li> <Li> 2018 Eastern Conference Second Round: Capitals won, 4--2 </Li> </Ul> </Td> </Tr> </Table> <Tr> <Td_colspan="2"> Washington Capitals Pittsburgh Penguins </Td> </Tr>

When was the last time the capitals beat the penguins in playoffs
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