Text annotations outside plot top and bottom?

[ignacio]

I'm trying to add some text annotations to this plot:

On the top I want to add "Negative impact" and "Positive impact" to the left and right of 0.5 respectively,
and on the bottom c("Very Unlikely", "Unlikely", "About as likely as not", "Likely", "Very Likely") for the respective areas. All these annotations should be outside the colored areas.

This is the code that I have, but is not doing anything close to what I want:

fake_data <- tibble(y = c("y1", "y2", "y3", "y4"),
                    x = c(0.12, 0.53, 0.76, 0.94))

likelihood_areas <- tibble(
  xmin = c(-Inf, 0.1, 0.33, 0.66, 0.9),
  xmax = c(0.1, 0.33, 0.66, 0.9, Inf),
  ymin = rep(-Inf, 5),
  ymax = rep(Inf, 5),
  likelihood = c("Very Unlikely", "Unlikely", "About as likely as not", "Likely", "Very Likely"),
  color = c("#2196f3", "#42a5f5", "#90caf9", "#42a5f5", "#2196f3")
)

ggplot() +
  geom_rect(data = likelihood_areas, aes(xmin = xmin, xmax = xmax, ymin = ymin, ymax = ymax, fill = color)) +
  geom_vline(xintercept = 0.5, linetype = "dashed") +
  geom_segment(data = fake_data, x = 0.5, aes(xend = x, y = y, yend = y), color = "grey", size = 1) +
  geom_point(data = fake_data, aes(x = x, y = y), size = 3) +
  scale_fill_identity() +
  theme_void() +
  scale_y_discrete(expand = expansion(mult = c(0, 0.3))) +
  # Add text annotations
  annotate("text", x = 0.25, y = 4.7, label = "Negative impact", hjust = 0) +
  annotate("text", x = 0.75, y = 4.7, label = "Positive impact", hjust = 1)

What am I missing? Thanks!

[startz]

annotate expands the size of the graph to keep the text inside.

As a kludge, you might use ggtitle with something like "Negative impact Positive impact" adding spaces between the headings to make things line up as you like.