| Año | Valor |
|---|---|
| 1981-01-01 | 27.217177 |
| 1982-01-01 | 230.417402 |
| 1983-01-01 | 172.749719 |
| 1984-01-01 | 1428.915644 |
| 1985-01-01 | 6987.876844 |
| 1986-01-01 | 184.371737 |
| 1987-01-01 | 94.944920 |
| 1988-01-01 | 27.839518 |
| 1989-01-01 | 21.433132 |
| 1990-01-01 | 52.865521 |
| 1991-01-01 | 50.732882 |
| 1992-01-01 | 34.473680 |
| 1993-01-01 | 33.702732 |
| 1994-01-01 | 24.211420 |
| 1995-01-01 | 7.657725 |
| 1996-01-01 | 39.837939 |
| 1997-01-01 | 18.964518 |
| 1998-01-01 | 13.423188 |
| 1999-01-01 | 3.230579 |
| 2000-01-01 | 1.553123 |
Fuente: World Bank