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:
| Member | Party | Term |
| --- | --- | --- |
| John Ryan | None | 1859–1864 |
| James Martin | None | 1864–1869 |
| James Watson | None | 1869–1880 |
| Member | Party | Term |
| James Carroll | Independent Protectionist | 1894–1895 |
| James Carroll | Protectionist | 1895–1901 |
| James Carroll | Progressive | 1901–1904 |
| Andrew Kelly | Labor | 1904–1913 |
| Thomas Brown | Labor | 1913–1917 |
| Ernest Buttenshaw | Nationalist | 1917–1920 |
| Member | Party | Term |
| Ernest Buttenshaw | Country | 1927–1938 |
| Griffith Evans | Country | 1938–1943 |
| John Chanter | Labor | 1943–1947 |
| Robert Medcalf | Country | 1947–1950 |
| Member | Party | Term |
| Ian Armstrong | National | 1981–2007 |
Question:
how long did ian armstrong serve?
Answer:
26 years