I have put together the following timeline using a number of sources and I hope to fill in the gaps and confirm the dates where possible.
There have been 30 Bun Throwing events since the tradition began in 1760 (19 are listed here).
First Bun Throwing
1760 – Accession of King George III
22 September 1761 – Marking King George III’s coronation
Loaves were distributed free in the market place - and the custom of throwing them from the roof of county hall seems to have developed from that.
1809 – Celebration of King George III’s recovery from illness
1819 – Celebration of King George III’s Golden Jubilee
1821 – George IV's coronation. The mayor and councillors threw 1000 buns
1831 – 500 cakes were thrown from the tops of houses
1837 – Abingdon Corporation accounts refer to buns being thrown 'according to ancient usage'.
1838 – A thousand buns were thrown to celebrate Queen Victoria’s Coronation
1946 – Celebration of Victory Day, 2500 buns are thrown
1956 – Fourth centenary of the borough
1956 – Queen Elizabeth II visited Abingdon to witness a special bun throwing
1977 – Queen Elizabeth II's Silver Jubilee, 2100 buns were thrown
Saturday 2 August or Monday 4 August (TBC) 1980 – 80th birthday of HRH Queen Elizabeth the Queen Mother
1997 – 50th wedding anniversary of the Queen and the Duke of Edinburgh
Saturday 17 June 2000 (6.30pm) – Celebrating the Millennium, 3000 buns were thrown
4 August 2000 (7pm) – The 100th birthday of HRH Queen Elizabeth the Queen Mother
Saturday 1 June 2002 (6pm) – The Queen's Golden Jubilee, 4000 buns were thrown (the buns were adorned with the letters 'EP')
10 June 2006 (5.30pm) – Abingdon celebrates the 450th Anniversary of the Charter of Incorporation granted by Queen Mary in 1556. June 10th is also Queen Elizabeth II’s Official Birthday. 4500 buns are thrown
15 September 2006 (11.30am – 12pm) – Abingdon continues the celebration of the 450th Anniversary of the Charter of Incorporation granted by Queen Mary in 1556 by holding the second bun throwing of the year in the presence of Her Royal Highness the Princess Royal. 450 buns are thrown