## ----include = FALSE---------------------------------------------------------- knitr::opts_chunk$set( collapse = TRUE, comment = "#>" ) ## ----setup-------------------------------------------------------------------- library(StateLevelForest) ## ----example, message=FALSE, warning=FALSE------------------------------------ # Load the StateLevelForest dataset data("StateLevelForest") # View the first few rows of the dataset head(StateLevelForest) ## ----plot, message=FALSE, warning=FALSE--------------------------------------- library(dplyr) library(ggplot2) MA_cover_relative_to_1630 <- StateLevelForest %>% filter(state == "Massachusetts") %>% mutate(X1630 = if_else(year == min(year), forest_thousands_of_acres, 0)) %>% mutate(X1630 = max(X1630)) %>% ungroup() %>% filter(year != min(year)) ggplot(MA_cover_relative_to_1630, aes(x = year, y = forest_thousands_of_acres)) + geom_hline(aes(yintercept = 0), color = NA, linewidth = 0) + geom_hline(aes(yintercept = X1630), color = "red", linewidth = 1) + geom_point() + geom_line() + scale_x_continuous(breaks = scales::pretty_breaks()) + scale_y_continuous(breaks = scales::pretty_breaks()) + labs(x = "Year", y = "Forest area (in thousands of acres)", title = "Massachusetts") + theme_minimal() + theme(axis.text.x = element_text(angle = 45, vjust = 0.5), aspect.ratio = 1)