| Acquisitions | Disposals | |
|---|---|---|
| 1982 | 
 | |
| 1983 | 
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| 1984 | 
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| 1989 | 
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| 1991 | 
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| 1993 | 
 | 
 | 
| 1995 | 
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| 1996 | 
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| 1997 | 
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| 1998 | 
 | 
 | 
| 1999 | 
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| 2000 | 
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| 2002 | 
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| 2003 | 
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| 2005 | 
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| 2006 | 
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| 2007 | 
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| 2008 | 
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| 2010 | 
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| 2011 | 
 | |
| 2012 | 
 | 
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| 2013 | 
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| 2014 | 
 | 
 | 
| 2015 | 
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| 2016 | 
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| 2017 | 
 | 
 | 
| 2018 | 
 | |
| 2019 | 
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| 2021 | 
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| 2022 | 
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