| Año | Valor |
|---|---|
| 1990-01-01 | 7.287767 |
| 1991-01-01 | 3.865363 |
| 1992-01-01 | 3.835795 |
| 1993-01-01 | 3.641556 |
| 1994-01-01 | 4.411089 |
| 1995-01-01 | 5.110800 |
| 1996-01-01 | 4.732803 |
| 1997-01-01 | 4.013825 |
| 1998-01-01 | 2.235948 |
| 1999-01-01 | 2.774976 |
| 2000-01-01 | 4.612828 |
| 2001-01-01 | 4.333687 |
| 2002-01-01 | 4.944851 |
| 2003-01-01 | 5.316278 |
| 2004-01-01 | 7.429981 |
| 2005-01-01 | 11.545221 |
| 2006-01-01 | 14.633457 |
| 2007-01-01 | 13.984935 |
| 2008-01-01 | 12.776687 |
| 2009-01-01 | 7.448517 |
Fuente: World Bank