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:
| Class | Type | Built | Number | Withdrawn |
| --- | --- | --- | --- | --- |
| Class 170 Turbostar | diesel multiple unit | 1999–2004 | 4.0 | 2005.0 |
| Class 222 Pioneer | diesel multiple unit | 2005 | 4.0 | 2009.0 |
| Class 86 | Electric locomotive | 1965–1966 | 1.0 | 2008.0 |
| Mark 3 Carriage | Passenger Carriage | 1975–1988 | 5.0 | 2008.0 |
| Mark 3 Carriage | Driving Van Trailer | 1988 | 1.0 | 2008.0 |
Question:
What is the sum of numbers that had a type of Driving Van Trailer?
Answer:
1.0