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:
| Year | Entrant | Chassis | Engine | Points |
| --- | --- | --- | --- | --- |
| 1972.0 | Scuderia Ferrari | Ferrari 312B2 | Ferrari Flat-12 | 1.0 |
| 1973.0 | Scuderia Ferrari | Ferrari 312B2 | Ferrari Flat-12 | 6.0 |
| 1973.0 | Scuderia Ferrari | Ferrari 312B3 | Ferrari Flat-12 | 6.0 |
| 1974.0 | Frank Williams Racing Cars | Iso-Marlboro FW | Cosworth V8 | 4.0 |
| 1975.0 | Frank Williams Racing Cars | Williams FW03 | Cosworth V8 | 0.0 |
| 1975.0 | Frank Williams Racing Cars | Williams FW04 | Cosworth V8 | 0.0 |
| 1975.0 | Fittpaldi-Copersucar | Fittipaldi FD03 | Cosworth V8 | 0.0 |
| 1976.0 | Ovoro March | March 761 | Cosworth V8 | 0.0 |
| 1976.0 | Walter Wolf Racing | Williams FW05 | Cosworth V8 | 0.0 |
| 1977.0 | Team Merzario | March 761B | Cosworth V8 | 0.0 |
| 1977.0 | Shadow Racing | Shadow DN8 | Cosworth V8 | 0.0 |
| 1978.0 | Team Merzario | Merzario A1 | Cosworth V8 | 0.0 |
| 1979.0 | Team Merzario | Merzario A1B | Cosworth V8 | 0.0 |
| 1979.0 | Team Merzario | Merzario A2 | Cosworth V8 | 0.0 |
| 1979.0 | Team Merzario | Merzario A4 | Cosworth V8 | 0.0 |
Question:
What is the average year for a merzario a2 chassis?
Answer:
1979.0