|   发表年代  |       数据收集年代  |       文献数量  |       样本量  |       男生/女生 (篇数)  |       城市/农村 (篇数)  |    
|   1999  |       1997  |       1  |       214  |       0  |       0  |    
|   2000  |       1998  |       1  |       549  |       1  |       0  |    
|   2003  |       2001  |       1  |       424  |       0  |       0  |    
|   2004  |       2002  |       2  |       662  |       1  |       1  |    
|   2005  |       2003  |       1  |       251  |       0  |       0  |    
|   2006  |       2004  |       1  |       202  |       1  |       0  |    
|   2007  |       2005  |       4  |       1462  |       4  |       2  |    
|   2008  |       2006  |       5  |       2083  |       5  |       3  |    
|   2009  |       2007  |       3  |       694  |       2  |       2  |    
|   2010  |       2008  |       14  |       4855  |       12  |       7  |    
|   2011  |       2009  |       14  |       5745  |       11  |       5  |    
|   2012  |       2010  |       11  |       6014  |       4  |       1  |    
|   2013  |       2011  |       9  |       3937  |       6  |       4  |    
|   2014  |       2012  |       7  |       3628  |       5  |       1  |    
|   2015  |       2013  |       16  |       9157  |       9  |       7  |    
|   2016  |       2014  |       15  |       8171  |       4  |       5  |    
|   2017  |       2015  |       20  |       10,205  |       10  |       5  |    
|   2018  |       2016  |       20  |       8809  |       10  |       4  |    
|   2019  |       2017  |       15  |       7689  |       8  |       3  |    
|   2020  |       2018  |       17  |       10,454  |       7  |       3  |    
|   总计  |       
  |       177  |       85,205  |       100  |       53  |