# Obtain the ARFIMA residuals
residuals <- data.frame(date = data$date[1:1000], residuals = arfima_best_fit$fit@fit['residuals']$residuals)

# Plot the arfima(1,d,1) residuals
ggplot(data=residuals, aes(x = date)) +
  # Choose the residuals as the y-axis variable
  geom_line(aes(y = residuals, color="Residuals")) +
  # Set the title, x and y labels
  ggtitle("Best ARFIMA model Residuals") + xlab("Date") + ylab("Residuals") + theme(plot.title = element_text(hjust = 0.5, size=30), legend.position="bottom", legend.text = element_text(size=20)) + scale_x_date(date_labels = "%b %y") +
  theme(
    axis.title.x = element_text(size = 20),
    axis.text.x = element_text(size = 20),
    axis.title.y = element_text(size = 20),
    axis.text.y = element_text(size = 20),)
ggsave("best-arfima-residuals.png")