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:
| Rider | Bike | Laps | Time | Grid |
| --- | --- | --- | --- | --- |
| Noriyuki Haga | Yamaha YZF-R1 | 18.0 | 32:05.318 | 1.0 |
| James Toseland | Honda CBR1000RR | 18.0 | +2.691 | 5.0 |
| Troy Bayliss | Ducati 999 F07 | 18.0 | +2.841 | 2.0 |
| Roberto Rolfo | Honda CBR1000RR | 18.0 | +3.188 | 10.0 |
| Max Biaggi | Suzuki GSX-R1000 K7 | 18.0 | +3.551 | 3.0 |
| Troy Corser | Yamaha YZF-R1 | 18.0 | +13.034 | 4.0 |
| Yukio Kagayama | Suzuki GSX-R1000 K7 | 18.0 | +17.246 | 8.0 |
| Régis Laconi | Kawasaki ZX-10R | 18.0 | +18.410 | 7.0 |
| Karl Muggeridge | Honda CBR1000RR | 18.0 | +29.017 | 6.0 |
| Jakub Smrž | Ducati 999 F05 | 18.0 | +29.686 | 17.0 |
| Michel Fabrizio | Honda CBR1000RR | 18.0 | +30.371 | 9.0 |
| Max Neukirchner | Suzuki GSX-R1000 K6 | 18.0 | +31.982 | 14.0 |
| Ruben Xaus | Ducati 999 F06 | 18.0 | +32.165 | 15.0 |
| Robertino Pietri | Yamaha YZF-R1 | 18.0 | +1:32.292 | 23.0 |
| Dean Ellison | Ducati 999RS | 18.0 | +1:41.840 | 21.0 |
| Marco Borciani | Ducati 999 F06 | 15.0 | Retirement | 16.0 |
| Steve Martin | Honda CBR1000RR | 11.0 | Retirement | 18.0 |
| Josh Brookes | Honda CBR1000RR | 9.0 | Retirement | 11.0 |
| Mauro Sanchini | Kawasaki ZX-10R | 7.0 | Retirement | 19.0 |
| Alex Polita | Suzuki GSX-R1000 K6 | 5.0 | Retirement | 20.0 |
| Marek Svoboda | Yamaha YZF-R1 | 1.0 | Retirement | 24.0 |
| Fonsi Nieto | Kawasaki ZX-10R | 1.0 | Retirement | 13.0 |
| Lorenzo Lanzi | Ducati 999 F07 | 0.0 | Retirement | 12.0 |
Question:
What is the mean number of laps when the grid was 8?
Answer:
18.0