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:
| Pos | No | Driver | Constructor | Laps | Time/Retired | Grid | Points |
| --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | 9 | Kimi Räikkönen | McLaren-Mercedes | 44 | 1:30:01.295 | 2 | 10 |
| 2 | 5 | Fernando Alonso | Renault | 44 | +28.394 | 4 | 8 |
| 3 | 3 | Jenson Button | BAR-Honda | 44 | +32.077 | 8 | 6 |
| 4 | 7 | Mark Webber | Williams-BMW | 44 | +1:09.167 | 9 | 5 |
| 5 | 2 | Rubens Barrichello | Ferrari | 44 | +1:18.136 | 12 | 4 |
| 6 | 11 | Jacques Villeneuve | Sauber-Petronas | 44 | +1:27.435 | 14 | 3 |
| 7 | 17 | Ralf Schumacher | Toyota | 44 | +1:27.574 | 5 | 2 |
| 8 | 18 | Tiago Monteiro | Jordan-Toyota | 43 | +1 Lap | 19 | 1 |
| 9 | 15 | Christian Klien | Red Bull-Cosworth | 43 | +1 Lap | 16 |  |
| 10 | 12 | Felipe Massa | Sauber-Petronas | 43 | +1 Lap | 7 |  |
| 11 | 19 | Narain Karthikeyan | Jordan-Toyota | 43 | +1 Lap | 20 |  |
| 12 | 21 | Christijan Albers | Minardi-Cosworth | 42 | +2 Laps | 18 |  |
| 13 | 20 | Robert Doornbos | Minardi-Cosworth | 41 | +3 Laps | 17 |  |
| 14 | 10 | Juan Pablo Montoya | McLaren-Mercedes | 40 | Collision | 1 |  |
| 15 | 8 | Antônio Pizzonia | Williams-BMW | 39 | Collision | 15 |  |
| Ret | 16 | Jarno Trulli | Toyota | 34 | Accident | 3 |  |
| Ret | 14 | David Coulthard | Red Bull-Cosworth | 18 | Engine | 11 |  |
| Ret | 1 | Michael Schumacher | Ferrari | 13 | Collision | 6 |  |
| Ret | 4 | Takuma Sato | BAR-Honda | 13 | Collision | 10 |  |
| Ret | 6 | Giancarlo Fisichella | Renault | 10 | Accident | 13 |  |
Question:
how many competitors in the 2005 belgian grand prix did not finish the race?
Answer:
5