a decreasing trendP = .026
The USA showed a decreasing trend ( P = .026), other 4 countries all showed increasing trends (all P < .001).
The USA showed a decreasing trend ( P = .026), other 4 countries all showed increasing trends (all P < .001).
[ 21 ] However, the USA did not show an increasing trend in the total outputs and even had a decreasing trend in the output per capita.