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:
| Number Range | Builder | Introduced | No. Built | Region | Withdrawn |
| --- | --- | --- | --- | --- | --- |
| 79958-59 | Bristol / Eastern Coach Works | 1958.0 | 2.0 | Scotland | 1966.0 |
| 79960-64 | WMD Donauwörth | 1958.0 | 5.0 | Eastern Region/London Midland | 1967.0 |
| 79965-69 | D Wickham & Co | 1958.0 | 5.0 | Scotland | 1966.0 |
| 79970-74 | Park Royal Vehicles | 1958.0 | 5.0 | London Midland / Scotland | 1968.0 |
| 79975-79 | AC Cars | 1958.0 | 5.0 | Scotland / Western Region | 1968.0 |
| 999507 Elliot | Wickham | 1958.0 | 1.0 | Departmental | 1997.0 |
Question:
What is the smallest introduced value?
Answer:
1958.0