总词频(每百万词)

1990~1994

1995~1999

2000~2004

2005~2009

2010~2014

2015~2019

quick

74.87

72.80

76.94

76.94

83.63

79.76

70.65

fast

95.75

91.42

98.34

99.28

100.01

98.63

88.94