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:
| District | Incumbent | Party | First elected | Result | Candidates |
| --- | --- | --- | --- | --- | --- |
| Virginia 2 | James Trezvant | Jacksonian | 1825 | Re-elected | James Trezvant (J) 100% |
| Virginia 3 | William S. Archer | Jacksonian | 1820 (special) | Re-elected | William S. Archer (J) 100% |
| Virginia 4 | Mark Alexander | Jacksonian | 1819 | Re-elected | Mark Alexander (J) 100% |
| Virginia 6 | Thomas Davenport | Jacksonian | 1825 | Re-elected | Thomas Davenport (J) 100% |
| Virginia 7 | Nathaniel H. Claiborne | Jacksonian | 1825 | Re-elected | Nathaniel H. Claiborne (J) 100% |
| Virginia 9 | Andrew Stevenson | Jacksonian | 1821 | Re-elected | Andrew Stevenson (J) 100% |
| Virginia 10 | William C. Rives | Jacksonian | 1823 | Re-elected | William C. Rives (J) 100% |
| Virginia 11 | Philip P. Barbour | Jacksonian | 1815 1827 | Re-elected | Philip P. Barbour (J) 100% |
| Virginia 12 | John Roane | Jacksonian | 1809 1827 | Re-elected | John Roane (J) 100% |
| Virginia 13 | John Taliaferro | Anti-Jacksonian | 1824 (special) | Re-elected | John Taliaferro (AJ) 61.8% Willoughby Newton 38.2% |
| Virginia 14 | Charles F. Mercer | Anti-Jacksonian | 1817 | Re-elected | Charles F. Mercer (AJ) 82.0% John Gibson 18.0% |
| Virginia 15 | John S. Barbour | Jacksonian | 1823 | Re-elected | John S. Barbour (J) 100% |
| Virginia 16 | William Armstrong | Anti-Jacksonian | 1825 | Re-elected | William Armstrong (AJ) 100% |
| Virginia 17 | Robert Allen | Jacksonian | 1827 | Re-elected | Robert Allen (J) 61.5% Samuel Kerceval 38.5% |
| Virginia 19 | William McCoy | Jacksonian | 1811 | Re-elected | William McCoy (J) 100% |
| Virginia 20 | John Floyd | Jacksonian | 1817 | Retired Jacksonian hold | Robert Craig (J) 55.0% Fleming B. Miller 45.0% |
Question:
How many people were first elected when john roane was the incumbent?
Answer:
1.0