| Año | Valor |
|---|---|
| 1986-01-01 | 11.971454 |
| 1987-01-01 | 12.167580 |
| 1988-01-01 | 11.679237 |
| 1989-01-01 | 13.064537 |
| 1990-01-01 | 14.192066 |
| 1991-01-01 | 14.528441 |
| 1992-01-01 | 17.562001 |
| 1993-01-01 | 20.377392 |
| 1994-01-01 | 18.976100 |
| 1995-01-01 | 17.706800 |
| 1996-01-01 | 18.832263 |
| 1997-01-01 | 19.688854 |
| 1998-01-01 | 19.676297 |
| 1999-01-01 | 20.504120 |
| 2000-01-01 | 20.553649 |
| 2001-01-01 | 24.244917 |
| 2002-01-01 | 28.784435 |
| 2003-01-01 | 28.207638 |
| 2004-01-01 | 27.211199 |
| 2005-01-01 | 25.983153 |
Fuente: World Bank