cor(Dogs$ranking[Dogs$year == "1992"], Dogs$ranking[Dogs$year == "1993"])
cor(Dogs$ranking[Dogs$year == "1997"], Dogs$ranking[Dogs$year == "1998"])
if (FALSE) {
library(ggplot2)
ggplot2::ggplot(data = Dogs, aes(x = reorder(breed, ranking), y = ranking)) + 
           geom_bar(stat = "identity") + 
           facet_grid(year ~. ) + 
           theme(axis.text.x  = element_text(angle = 85, vjust = 0.5)) 
}
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