主成分\年份

2000

2005

2010

2015

2020

2005

PC1

85.04%

79.78%

89.21%

82.60%

83.82%

PC2

8.81%

12.08%

5.75%

10.67%

10.01%

PC3

4.93%

6.93%

2.05%

5.66%

4.92%

PC4

1.22%

1.21%

1.08%

0.63%

1.25%