Geoms for Playfair-Style Charts

Currently provides geom_balance_of_trade(), a 'ggplot2' layer that fills the area between exports and imports series (with automatic crossing detection and conditional coloring for surplus vs. deficit), and overlays lines and points by default.

title: "README" author: "Derek Stevens" date: "2025-07-20" output: html_document

ggplayfair

About:

Makes Playfair graphs easier to create using ggplot.

How to Use ggplayfair

This section provides a quickstart guide for installing and using the ggplayfair package to create balance of trade charts with ggplot2.

Installation

Install the latest CRAN release:

#install.packages("ggplayfair")

Or install the development version from GitHub:

# If you don’t have devtools installed:
#install.packages("devtools")
library(devtools)

devtools::install_github("DerekStevens99/ggplayfair")

Basic Usage

Load the package and prepare your data frame. Your data should include:

• x: the x-axis variable (e.g., year, quarter)
• exports: numeric values representing deficit lessening activity.
• imports: numeric values representing deficit driving activity.

library(ggplot2)
library(ggplayfair)

# sample data
df <- data.frame(
  year    = 2000:2010,
  exports = c(50, 55, 60, 58, 62, 65, 63, 67, 70, 72, 75),
  imports = c(45, 50, 52, 55, 58, 60, 100, 120, 68, 70, 74)
)

# one line - geom_balance_of_trade - builds the Playfair‐style ribbon + lines + points
ggplot(df, aes(x = year, exports = exports, imports = imports)) +
  geom_balance_of_trade(alpha = 0.6) +
  scale_fill_manual(
    values = c(surplus = "forestgreen", deficit = "firebrick")
  ) +
  labs(
    title    = "Balance of Trade",
    subtitle = "Exports vs Imports, 2000–2010"
  ) +
  theme_minimal()

Customization

• Colors: override default with scale_fill_manual() or any scale_fill_*().
• Themes: apply any ggplot2 theme (e.g., theme_classic(), theme_dark()).
• Labels: customize with labs() or scale_x_*(), scale_y_*() functions.