年代

Age

品种个数

Number varieties

变异区间

Variation interval/%

变异幅度

Variance/%

平均值

Average/%

1985~1990

10

62.80~66.30

3.50

63.96

1991~1995

10

59.37~68.40

9.03

63.54

1996~2000

9

60.73~65.68

4.95

63.76

2001~2005

15

56.10~66.09

9.99

63.10

2006~2010

17

58.28~64.45

6.17

62.01

2011~2015

21

58.05~65.02

6.97

61.69

2016~2020

43

58.70~65.75

7.05

62.07

1985~2020

125

56.10~68.40

12.30

62.51