library(ggplot2)
df <- read.csv('seats-votes.csv')
df$year <- as.factor(df$year)

# scatterplot w/o jitter
png("f1.png",width=672,height=671)
qplot(year,voteshare,data=df,geom="point",alpha=I(.15),xlab="Year", ylab="Democratic Vote Share (%)",main="Democratic Vote Share US House 2002-2008")+ geom_hline(yintercept=50,colour="gray50")
dev.off()

# scatterplot w/ jitter
png("f2.png",width=672,height=671)
qplot(year,voteshare,data=df,geom="jitter",alpha=I(.35),xlab="Year", ylab="Democratic Vote Share (%)",main="Democratic Vote Share US House 2002-2008") + geom_hline(yintercept=50,colour="gray50")
dev.off()

# simple histogram
png("f3.png",width=672,height=671)
qplot(voteshare,data=df,geom="histogram",binwidth=2,xlab="Democratic Vote Share (%)", ylab="Count",main="Democratic Vote Share US House 2002-2008") + facet_wrap(~year,nrow=2) + geom_vline(xintercept=50,colour="gray50")
dev.off()

# density plot
png("f4.png",width=672,height=671)
qplot(voteshare,data=df, geom=c("density", "rug"),xlab="Democratic Vote Share (%)", ylab="Density",main="Democratic Vote Share US House 2002-2008") + facet_wrap(~year,nrow=2)+ geom_vline(xintercept=50,colour="gray50")
dev.off()

# min/max boxplot
png("f5.png",width=672,height=671)
qplot(year,voteshare,data=df,geom="boxplot",xlab="Year", ylab="Democratic Vote Share (%)",main="Democratic Vote Share US House 2002-2008")+ geom_hline(yintercept=50,colour="gray50")
dev.off()