| Año | Valor |
|---|---|
| 1991-01-01 | 4.799745 |
| 1992-01-01 | 12.882886 |
| 1993-01-01 | 35.035554 |
| 1994-01-01 | 45.742677 |
| 1995-01-01 | 31.758235 |
| 1996-01-01 | 27.370244 |
| 1997-01-01 | 54.441169 |
| 1998-01-01 | 54.544488 |
| 1999-01-01 | 34.822839 |
| 2000-01-01 | 24.600401 |
| 2001-01-01 | 20.513249 |
| 2002-01-01 | 28.585754 |
| 2003-01-01 | 36.954540 |
| 2004-01-01 | 43.507658 |
| 2005-01-01 | 50.864531 |
| 2006-01-01 | 63.683603 |
| 2007-01-01 | 82.124407 |
| 2008-01-01 | 94.993619 |
| 2009-01-01 | 107.367509 |
| 2010-01-01 | 124.542664 |
Fuente: World Bank