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:
| IME Exchange (Including spot, credit and forward transactions) | 2007/08 | 2008/09 | 2009/10 | 2010/11 | 2011/12 |
| --- | --- | --- | --- | --- | --- |
| Agricultural - Volume (thousand tons) | 273.0 | 173.5 | 175.2 | 1,633.9 | 550.0 |
| Agricultural - Value (billion rials) | 772.6 | 3,729.7 | 484.8 | 3,729.0 | 3,793.0 |
| Manufacturing and Metal - Volume (thousand tons) | 6,443.8 | 6,679.7 | 7,438.5 | 8,694.0 | 11,685.0 |
| Manufacturing and Metal - Value (billion rials) | 58,044.2 | 62,120.6 | 53,842.0 | 75,235.5 | 102,356.0 |
| Oil and Petrochemical - Volume (thousand tons) | 89.7 | 4,339.2 | 7,052.9 | 6,662.6 | 8,117.0 |
| Oil and Petrochemical - Value (billion rials) | 352.7 | 19,921.0 | 36,450.7 | 41,478.0 | 64,370.0 |
| Grand Total - Volume (thousand tons) | 6,806.5 | 11,192.4 | 14,666.6 | 16,990.5 | 20,351.0 |
| Grand Total - Value (billion rials) | 59,169.4 | 82,685.3 | 90,777.5 | 120,443.2 | 170,519.0 |
Question:
in how many years was the value of agriculture, in billion rials, greater than 500 in iran?
Answer:
4