graphics, zoo, ggplot2 (>= 0.9), reshape2
graphics, grDevices, stats, ggplot2 (>= 0.9), reshape2
graphics, grDevices, stats, ggplot2 (>= 1.0), reshape2
graphics, grDevices, methods, stats, utils, ggplot2 (>= 1.0),
knitr, reshape2, zoo
graphics, grDevices, methods, stats, ggplot2 (>= 1.0), knitr
(>= 1.1), reshape2, zoo