| Año | Valor |
|---|---|
| 1985-01-01 | 7.810286 |
| 1986-01-01 | 6.192639 |
| 1987-01-01 | 5.185371 |
| 1988-01-01 | 6.124569 |
| 1989-01-01 | 6.239698 |
| 1990-01-01 | 6.530300 |
| 1991-01-01 | 7.858955 |
| 1992-01-01 | 8.781583 |
| 1993-01-01 | 9.592321 |
| 1994-01-01 | 10.934078 |
| 1995-01-01 | 10.675894 |
| 1996-01-01 | 13.358569 |
| 1997-01-01 | 13.450198 |
| 1998-01-01 | 13.036795 |
| 1999-01-01 | 10.991747 |
| 2000-01-01 | 12.718548 |
| 2001-01-01 | 12.116961 |
| 2002-01-01 | 13.566160 |
| 2003-01-01 | 13.519608 |
| 2004-01-01 | 14.538151 |
Fuente: World Bank