| Año | Valor |
|---|---|
| 1981-01-01 | 29.486094 |
| 1982-01-01 | 158.283333 |
| 1983-01-01 | 265.197668 |
| 1984-01-01 | 1443.397136 |
| 1985-01-01 | 12338.660141 |
| 1986-01-01 | 230.105222 |
| 1987-01-01 | 14.584194 |
| 1988-01-01 | 17.523337 |
| 1989-01-01 | 13.186421 |
| 1990-01-01 | 16.267942 |
| 1991-01-01 | 17.689440 |
| 1992-01-01 | 13.199204 |
| 1993-01-01 | 6.557158 |
| 1994-01-01 | 7.952208 |
| 1995-01-01 | 11.427282 |
| 1996-01-01 | 11.580207 |
| 1997-01-01 | 5.705043 |
| 1998-01-01 | 7.051127 |
| 1999-01-01 | 2.411566 |
| 2000-01-01 | 5.195405 |
Fuente: World Bank