| Año | Valor |
|---|---|
| 1985-01-01 | 8.258114 |
| 1986-01-01 | 8.019955 |
| 1987-01-01 | 7.949053 |
| 1988-01-01 | 7.280551 |
| 1989-01-01 | 7.094743 |
| 1990-01-01 | 7.236225 |
| 1991-01-01 | 7.932730 |
| 1992-01-01 | 8.899789 |
| 1993-01-01 | 9.516345 |
| 1994-01-01 | 10.045468 |
| 1995-01-01 | 9.722329 |
| 1996-01-01 | 12.293853 |
| 1997-01-01 | 12.620346 |
| 1998-01-01 | 13.546529 |
| 1999-01-01 | 12.039785 |
| 2000-01-01 | 12.330803 |
| 2001-01-01 | 11.782546 |
| 2002-01-01 | 13.184105 |
| 2003-01-01 | 12.973000 |
| 2004-01-01 | 15.016349 |
Fuente: World Bank