When a team eliminates their opponent using the minimum number of games without sustaining a single loss in a multi-game series they are said to have swept the other team. In the Stanley Cup Playoffs that means winning the first four games of a best-of-seven series.
Of the NHL's 591 best-of-seven playoff series since the league's origins through 2012, 108 (18%) have ended in a sweep. The most sweeps in a single postseason during this span is five (1969, 1992). Only twice since all postseason series were expanded to best-of-seven in 1987 has a Stanley Cup Playoff series gone without a sweep (1991, 2002).
Over the past 25 postseasons (since the 1987 expansion to best-of-seven series), a sweep has resulted in 56 of 375 series, representing 1 in 6.7 (15%) of all playoff series. The chart below describes playoff sweeps by year, noting the number and round in which sweep(s) occurred.
|Year: Sweeps (Round)||Year: Sweeps (Round)|
|1987: 3 (2P, 1Q)||2002: 0|
|1988: 2 (1Q, F)||2003: 2 (1P, 1S)|
|1989: 3 (2P, 1Q)||2004: 1 (1Q)|
|1990: 2 (1P, 1S)||2006: 2 (1P, 1Q)|
|1991: 0||2007: 1 (1P)|
|1992: 5 (2Q, 2S, F)||2008: 2 (1P, 1Q)|
|1993: 3 (2P, 1Q)||2009: 4 (3P, 1S)|
|1994: 2 (2P)||2010: 1 (1S)|
|1995: 4 (3Q, F)||2011: 3 (1P, 2Q)|
|1996: 2 (1P, F)||2012: 1 (1Q)|
|1997: 2 (1Q, F)|
|1998: 3 (1P, 1Q, F)|
|1999: 3 (3P)|
|2000: 2 (2P)|
|2001: 3 (2P, 1Q)|
(P = Preliminary, Q = Quarterfinal, S = Semifinal, F = Final)
Breaking it down by round, the most sweeps on a percentage basis have happened in the Stanley Cup Final (6/25 = 24%), though no team has been swept there since 1998 when the Detroit Red Wings disposed off the Washington Capitals. The Quarterfinal (18/100 = 18%), Preliminary (26/200 = 13%) and Semifinal (6/50 = 12%) rounds follow with a historically significant but decreasing likelihood of sweep.
The first sweep of the 2013 Playoffs was on May 7th when the San Jose Sharks swept their opening round series against the Vancouver Canucks. The second sweep of the postseason came one month later on June 7th when the Boston Bruins completed a rare PERFECT sweep of the Pittsburgh Penguins, NEVER trailing in any game during the series. Beware of the brooms.