| Value | Category | Cases | |
|---|---|---|---|
| 1980 | 10 | 
                                                                 
                                    
                                    0.1%
                                 
                                                             | 
                                                        
                    |
| 1983 | 39 | 
                                                                 
                                    
                                    0.3%
                                 
                                                             | 
                                                        
                    |
| 1984 | 56 | 
                                                                 
                                    
                                    0.4%
                                 
                                                             | 
                                                        
                    |
| 1985 | 128 | 
                                                                 
                                    
                                    0.9%
                                 
                                                             | 
                                                        
                    |
| 1986 | 180 | 
                                                                 
                                    
                                    1.3%
                                 
                                                             | 
                                                        
                    |
| 1987 | 160 | 
                                                                 
                                    
                                    1.2%
                                 
                                                             | 
                                                        
                    |
| 1988 | 271 | 
                                                                 
                                    
                                    2%
                                 
                                                             | 
                                                        
                    |
| 1989 | 267 | 
                                                                 
                                    
                                    1.9%
                                 
                                                             | 
                                                        
                    |
| 1990 | 353 | 
                                                                 
                                    
                                    2.5%
                                 
                                                             | 
                                                        
                    |
| 1991 | 384 | 
                                                                 
                                    
                                    2.8%
                                 
                                                             | 
                                                        
                    |
| 1992 | 414 | 
                                                                 
                                    
                                    3%
                                 
                                                             | 
                                                        
                    |
| 1993 | 473 | 
                                                                 
                                    
                                    3.4%
                                 
                                                             | 
                                                        
                    |
| 1994 | 463 | 
                                                                 
                                    
                                    3.3%
                                 
                                                             | 
                                                        
                    |
| 1995 | 450 | 
                                                                 
                                    
                                    3.2%
                                 
                                                             | 
                                                        
                    |
| 1996 | 410 | 
                                                                 
                                    
                                    3%
                                 
                                                             | 
                                                        
                    |
| 1997 | 496 | 
                                                                 
                                    
                                    3.6%
                                 
                                                             | 
                                                        
                    |
| 1998 | 519 | 
                                                                 
                                    
                                    3.7%
                                 
                                                             | 
                                                        
                    |
| 1999 | 539 | 
                                                                 
                                    
                                    3.9%
                                 
                                                             | 
                                                        
                    |
| 2000 | 505 | 
                                                                 
                                    
                                    3.6%
                                 
                                                             | 
                                                        
                    |
| 2001 | 491 | 
                                                                 
                                    
                                    3.5%
                                 
                                                             | 
                                                        
                    |
| 2002 | 497 | 
                                                                 
                                    
                                    3.6%
                                 
                                                             | 
                                                        
                    |
| 2003 | 539 | 
                                                                 
                                    
                                    3.9%
                                 
                                                             | 
                                                        
                    |
| 2004 | 441 | 
                                                                 
                                    
                                    3.2%
                                 
                                                             | 
                                                        
                    |
| 2005 | 534 | 
                                                                 
                                    
                                    3.8%
                                 
                                                             | 
                                                        
                    |
| 2006 | 520 | 
                                                                 
                                    
                                    3.7%
                                 
                                                             | 
                                                        
                    |
| 2007 | 428 | 
                                                                 
                                    
                                    3.1%
                                 
                                                             | 
                                                        
                    |
| 2008 | 604 | 
                                                                 
                                    
                                    4.3%
                                 
                                                             | 
                                                        
                    |
| 2009 | 531 | 
                                                                 
                                    
                                    3.8%
                                 
                                                             | 
                                                        
                    |
| 2010 | 524 | 
                                                                 
                                    
                                    3.8%
                                 
                                                             | 
                                                        
                    |
| 2011 | 457 | 
                                                                 
                                    
                                    3.3%
                                 
                                                             | 
                                                        
                    |
| 2012 | 437 | 
                                                                 
                                    
                                    3.1%
                                 
                                                             | 
                                                        
                    |
| 2013 | 405 | 
                                                                 
                                    
                                    2.9%
                                 
                                                             | 
                                                        
                    |
| 2014 | 386 | 
                                                                 
                                    
                                    2.8%
                                 
                                                             | 
                                                        
                    |
| 2015 | 371 | 
                                                                 
                                    
                                    2.7%
                                 
                                                             | 
                                                        
                    |
| 2016 | 262 | 
                                                                 
                                    
                                    1.9%
                                 
                                                             | 
                                                        
                    |
| 2017 | 228 | 
                                                                 
                                    
                                    1.6%
                                 
                                                             | 
                                                        
                    |
| 2018 | 67 | 
                                                                 
                                    
                                    0.5%
                                 
                                                             | 
                                                        
                    |
| 9999 | No response | 51 | 
                                                                 
                                    
                                    0.4%
                                 
                                                             |