Purchasing power parities (PPP) conversion factor, local currency unit to international dollar
| Year | Value | Footnotes |
|---|---|---|
| 1990 | 3.92 | |
| 1991 | 3.94 | |
| 1992 | 3.82 | |
| 1993 | 3.75 | |
| 1994 | 3.68 | |
| 1995 | 3.75 | |
| 1996 | 3.69 | |
| 1997 | 3.61 | |
| 1998 | 3.54 | |
| 1999 | 3.42 | |
| 2000 | 3.27 | |
| 2001 | 3.14 | |
| 2002 | 3.1 | |
| 2003 | 3.05 | |
| 2004 | 2.98 | |
| 2005 | 2.9 | |
| 2006 | 2.87 | |
| 2007 | 2.91 | |
| 2008 | 3.08 | |
| 2009 | 3.25 |
