| Año | Valor |
|---|---|
| 1985-01-01 | 60.129032 |
| 1986-01-01 | 35.698776 |
| 1987-01-01 | 30.347582 |
| 1988-01-01 | 35.550921 |
| 1989-01-01 | 35.342309 |
| 1990-01-01 | 34.583425 |
| 1991-01-01 | 36.989837 |
| 1992-01-01 | 39.017356 |
| 1993-01-01 | 34.998173 |
| 1994-01-01 | 43.358231 |
| 1995-01-01 | 45.017413 |
| 1996-01-01 | 50.205647 |
| 1997-01-01 | 53.730284 |
| 1998-01-01 | 52.911638 |
| 1999-01-01 | 43.751172 |
| 2000-01-01 | 50.420909 |
| 2001-01-01 | 48.646675 |
| 2002-01-01 | 47.781456 |
| 2003-01-01 | 45.562588 |
| 2004-01-01 | 45.306271 |
Fuente: World Bank