| Año | Valor |
|---|---|
| 1987-01-01 | 0.698985 |
| 1988-01-01 | 0.732487 |
| 1989-01-01 | 0.765989 |
| 1990-01-01 | 0.799490 |
| 1991-01-01 | 0.832992 |
| 1992-01-01 | 0.866493 |
| 1993-01-01 | 0.899995 |
| 1994-01-01 | 0.933496 |
| 1995-01-01 | 0.966998 |
| 1996-01-01 | 1.000500 |
| 1997-01-01 | 1.034001 |
| 1998-01-01 | 1.067503 |
| 1999-01-01 | 1.101004 |
| 2000-01-01 | 1.109500 |
| 2001-01-01 | 1.117995 |
| 2002-01-01 | 1.126490 |
| 2003-01-01 | 1.134986 |
| 2004-01-01 | 1.143481 |
| 2005-01-01 | 1.151976 |
| 2006-01-01 | 1.160472 |
Fuente: World Bank