library(openxlsx)
sample1<-read.xlsx("http://kanggc.iptime.org/book/data/sample1-n.xlsx") 
year<-sample1$year
gdp<-sample1$gdp
consumption<-sample1$consumption
gdp
consumption
par(mfrow=c(1,2)) 
hist(gdp)
hist(consumption, breaks=8, col="red")