| Año | Valor |
|---|---|
| 1985-01-01 | 3.172979 |
| 1986-01-01 | 2.375881 |
| 1987-01-01 | 4.266404 |
| 1988-01-01 | 8.275073 |
| 1989-01-01 | 10.404175 |
| 1990-01-01 | 9.243848 |
| 1991-01-01 | 9.547341 |
| 1992-01-01 | 9.003675 |
| 1993-01-01 | 8.837429 |
| 1994-01-01 | 4.934803 |
| 1995-01-01 | 4.215061 |
| 1996-01-01 | 9.027672 |
| 1997-01-01 | 9.974123 |
| 1998-01-01 | 9.740178 |
| 1999-01-01 | 12.261336 |
| 2000-01-01 | 11.299038 |
| 2001-01-01 | 10.019612 |
| 2002-01-01 | 11.258736 |
| 2003-01-01 | 11.124125 |
| 2004-01-01 | 11.409524 |
Fuente: World Bank