| Año | Valor |
|---|---|
| 1990-01-01 | 2.257000 |
| 1991-01-01 | 2.372500 |
| 1992-01-01 | 2.341600 |
| 1993-01-01 | 2.704200 |
| 1994-01-01 | 2.811300 |
| 1995-01-01 | 3.126200 |
| 1996-01-01 | 3.242100 |
| 1997-01-01 | 3.074000 |
| 1998-01-01 | 3.172800 |
| 1999-01-01 | 3.176300 |
| 2000-01-01 | 2.640400 |
| 2001-01-01 | 2.647100 |
| 2002-01-01 | 2.724800 |
| 2003-01-01 | 2.923800 |
| 2004-01-01 | 3.226400 |
| 2005-01-01 | 3.452700 |
| 2006-01-01 | 3.992200 |
| 2007-01-01 | 4.513800 |
| 2008-01-01 | 5.087000 |
| 2009-01-01 | 5.538600 |
Fuente: World Bank