A round of 16 over a best of 25 frames first started in 1980. Here's a list of how many (out of 8) matches ended with a session to spare each year. Any year when it didn't happen is omitted.
1981 - 2 (13-2, 13-3)
1983 - 1 (13-3)
1985 - 1 (13-3)
1988 - 2 (13-1, 13-1)
1989 - 2 (13-3, 13-3)
1991 - 1 (13-1)
1994 - 3 (13-2, 13-3, 13-3)
1997 - 1 (13-3)
1998 - 1 (13-3)
2000 - 1 (13-1)
2002 - 5 (13-2, 13-2, 13-3, 13-3, 13-3)
2003 - 1 (13-2)
2005 - 1 (13-3)
2006 - 1 (13-2)
2009 - 1 (13-3)
2013 - 1 (13-3)
2017 - 1 (13-3)
It's only happened twice since 2009. Michael White beat Dechawat Poomjaeng 13-3 in 2013 and Stephen Maguire bear Rory McLeod 13-3 this year. The year for crushing victories was 2002. O'Sullivan over Milkins and Higgins over Dott (13-2) and Hendry over Davies, Lee over Hann, and Stevens over White (13-3)
It's happened 26 times in 38 years. So 26 times out 304. 8.55% of the time. So if you can get 15 to 1 odds it's a good bet, though the recent trend seems to be in favour of 2nd round matches being more competitive.
1981 - 2 (13-2, 13-3)
1983 - 1 (13-3)
1985 - 1 (13-3)
1988 - 2 (13-1, 13-1)
1989 - 2 (13-3, 13-3)
1991 - 1 (13-1)
1994 - 3 (13-2, 13-3, 13-3)
1997 - 1 (13-3)
1998 - 1 (13-3)
2000 - 1 (13-1)
2002 - 5 (13-2, 13-2, 13-3, 13-3, 13-3)
2003 - 1 (13-2)
2005 - 1 (13-3)
2006 - 1 (13-2)
2009 - 1 (13-3)
2013 - 1 (13-3)
2017 - 1 (13-3)
It's only happened twice since 2009. Michael White beat Dechawat Poomjaeng 13-3 in 2013 and Stephen Maguire bear Rory McLeod 13-3 this year. The year for crushing victories was 2002. O'Sullivan over Milkins and Higgins over Dott (13-2) and Hendry over Davies, Lee over Hann, and Stevens over White (13-3)
It's happened 26 times in 38 years. So 26 times out 304. 8.55% of the time. So if you can get 15 to 1 odds it's a good bet, though the recent trend seems to be in favour of 2nd round matches being more competitive.
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