library(openxlsx)
library(fBasics)

df<-read.xlsx("http://kanggc.iptime.org/book/data/describe-e.xlsx")
df_dat<-data.matrix(df)

cpi<-df_dat[,2]
interest<-df_dat[,3]
gdp<-df_dat[,4]
deflator<-df_dat[,5]

df_new<-cbind(cpi, interest, gdp, deflator)
df_new
summary(df_new)

(var<-var(df_new))

(sd1<-sd(cpi))
(sd2<-sd(interest))
(sd3<-sd(gdp))
(sd4<-sd(deflator))

basicStats(df_new)