| Año | Valor |
|---|---|
| 1996-01-01 | 4.312231 |
| 1997-01-01 | 4.190767 |
| 1998-01-01 | 4.181205 |
| 1999-01-01 | 3.052713 |
| 2000-01-01 | 3.310101 |
| 2001-01-01 | 3.111693 |
| 2002-01-01 | 2.857958 |
| 2003-01-01 | 3.439216 |
| 2004-01-01 | 3.119258 |
| 2005-01-01 | 3.110022 |
| 2006-01-01 | 2.831428 |
| 2007-01-01 | 2.133396 |
| 2008-01-01 | 2.942820 |
| 2009-01-01 | 1.609941 |
| 2010-01-01 | 1.602447 |
| 2011-01-01 | 1.006190 |
| 2012-01-01 | 1.739033 |
| 2013-01-01 | 0.990353 |
| 2014-01-01 | 1.184872 |
| 2015-01-01 | 1.651901 |
Fuente: World Bank