| Year | Import | Export | Net-import | Year | Import | Export | Net-import |
| 1990 | 152.79 | 40.01 | 112.78 | 2002 | 539.11 | 126.87 | 412.24 |
| 1991 | 152.85 | 80.9 | 71.95 | 2003 | 437.34 | 90.74 | 246.2 |
| 1992 | 136.3 | 100.235 | 35.6 | 2004 | 882.65 | 42.81 | 839.84 |
| 1993 | 75.87 | 110.42 | −34.55 | 2005 | 814.22 | 86.93 | 727.28 |
| 1994 | 91.87 | 96.18 | −4.76 | 2006 | 1023.99 | 56.38 | 967.63 |
| 1995 | 190.42 | 5.39 | 185.03 | 2007 | 1080.37 | 88.83 | 991.54 |
| 1996 | 116.77 | 6.39 | 110.38 | 2012 | 1173.47 | 26.57 | 1146.9 |
| 1997 | 65.18 | 66.56 | −1.39 | 2009 | 1423.33 | 17.92 | 1413.41 |
| 1998 | 151.57 | 100.99 | 50.57 | 2010 | 2124.73 | 49.09 | 2069.64 |
| 1999 | 127.11 | 65 | 61.839 | 2011 | 2046.26 | 56.08 | 1990.18 |
| 2000 | 175.46 | 118.13 | 57.33 | 2012 | 2239.27 | 54.39 | 2264.88 |
| 2001 | 406.77 | 76.23 | 330.46 | Total | 15715.7 | 1563.125 | 14044.98 |