>dp4<-subset(dp,select=c(datetime,pct_chg))

>dp4<-dp4[complete.cases(dp4),]

>dp43<-filter(dp4,datetime=="2003-1-6")

>ggplot(dp43,aes(x=pct_chg))+

+geom_histogram(bins=20,fill="cornsilk",colour="grey60")+

+geom_density()