| Año | Valor |
|---|---|
| 1990-01-01 | 0.862463 |
| 1991-01-01 | 0.618764 |
| 1992-01-01 | 0.555818 |
| 1993-01-01 | 0.635138 |
| 1994-01-01 | 0.536023 |
| 1995-01-01 | 0.448012 |
| 1996-01-01 | 0.405157 |
| 1997-01-01 | 0.385552 |
| 1998-01-01 | 0.264054 |
| 1999-01-01 | 0.320801 |
| 2000-01-01 | 0.772562 |
| 2001-01-01 | 1.104339 |
| 2002-01-01 | 1.100887 |
| 2003-01-01 | 1.021227 |
| 2004-01-01 | 1.317968 |
| 2005-01-01 | 2.836157 |
| 2006-01-01 | 3.558061 |
| 2007-01-01 | 3.985609 |
| 2008-01-01 | 3.640084 |
| 2009-01-01 | 3.305643 |
Fuente: World Bank