Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| # | Name\n(Birth–Death) | Took office | Left office | Monarch | Prime Minister |
| --- | --- | --- | --- | --- | --- |
| 1 | The Viscount Gladstone\n(1854–1930) | 31 May 1910 | 8 September 1914 | George V | Botha |
| 2 | The Viscount Buxton\n(1853–1934) | 8 September 1914 | 17 November 1920 | George V | Botha |
| 3 | HRH Prince Arthur of Connaught\n(1883–1938) | 17 November 1920 | 21 January 1924 | George V | Smuts |
| 4 | The Earl of Athlone\n(1874–1957) | 21 January 1924 | 26 January 1931 | George V | Smuts |
| 5 | The Earl of Clarendon\n(1877–1955) | 26 January 1931 | 5 April 1937 | George V | Hertzog |
| 6 | Sir Patrick Duncan\n(1870–1943) | 5 April 1937 | 17 July 1943 | George VI | Hertzog |
| — | Nicolaas Jacobus de Wet\n(1873–1960)\n(Officer Administering the Government) | 17 July 1943 | 1 January 1946 | George VI | Smuts |
| 7 | Gideon Brand van Zyl\n(1873–1956) | 1 January 1946 | 1 January 1951 | George VI | Smuts |
| 8 | Ernest George Jansen\n(1881–1959) | 1 January 1951 | 25 November 1959 | George VI | Malan |
| — | Lucas Cornelius Steyn\n(1903–1976)\n(Officer Administering the Government) | 26 November 1959 | 11 December 1959 | Elizabeth II | Verwoerd |
| 9 | Charles Robberts Swart\n(1894–1982) | 11 December 1959 | 30 April 1961 | Elizabeth II | Verwoerd |
| — | Lucas Cornelius Steyn\n(1903–1976)\n(Officer Administering the Government) | 30 April 1961 | 31 May 1961 | Elizabeth II | Verwoerd |
Question:
how many total years did sir patrick duncan serve in office?
Answer:
6