Using Table 1, calculate the change in Indonesia's terms of trade between 2017 and 2018.
Table 1 – Indonesia's export prices, import prices, export volumes, import volumes and current account position, 2016–20
| Year | Index of export prices | Index of import prices | Index of export volumes | Index of import volumes | Balance on the current account of the balance of payments as % of GDP |
|---|---|---|---|---|---|
| 2016 | 98 | 99 | 104 | 102 | –1.8 |
| 2017 | 104 | 101 | 112 | 108 | –2.1 |
| 2018 | 110 | 105 | 115 | 112 | –3.0 |
| 2019 | 108 | 109 | 118 | 114 | –2.7 |
| 2020 | 105 | 112 | 110 | 107 | –1.5 |
