| Año | Valor |
|---|---|
| 1990-01-01 | -91.590738 |
| 1991-01-01 | -90.818104 |
| 1992-01-01 | -80.389417 |
| 1993-01-01 | -72.950996 |
| 1994-01-01 | -69.005949 |
| 1995-01-01 | -55.167434 |
| 1996-01-01 | -42.702088 |
| 1997-01-01 | -27.678749 |
| 1998-01-01 | -26.188833 |
| 1999-01-01 | -18.291124 |
| 2000-01-01 | -49.650560 |
| 2001-01-01 | -82.382440 |
| 2002-01-01 | -73.490177 |
| 2003-01-01 | -94.161150 |
| 2004-01-01 | -145.621466 |
| 2005-01-01 | -163.593527 |
| 2006-01-01 | -171.323974 |
| 2007-01-01 | -180.911410 |
| 2008-01-01 | -183.610357 |
| 2009-01-01 | -136.604641 |
Fuente: World Bank