Your coffee—be it morning, afternoon, or after dinner—can take a wide variety of forms: regular coffee, single- or double-shot espresso, and ice cold latte, to name just a few. And even a regular coffee can be prepared using many different methods and equipment, from the old-school percolator, the more-modern coffee maker, or the trendier vacuum pot and the Chemex. International variations, of course, include the use of the French press and the Italian or moka pot, as well as styles such as Turkish coffee, café cubano, and, a personal favorite, the Costa Rican café de chorreador.
A lesser known fact is that the coffee beans needed for any of the above can come from two different species of coffee: robusta (coffea canephora) and arabica (coffea arabica). The former is a sturdy tree with a high yield of beans with high acidity and bitterness and low aroma. The latter is a shrub less resistant to disease with a lower yield of beans with lower acidity and bitterness and stronger aroma.
Arabica coffee is generally considered much higher quality than robusta. This can be confirmed by looking at their market prices, which can be found in FRED. The graph above shows the global monthly bulk prices (US$ per 100 lb.) of the two types of coffee beans: the red line for arabica and the blue line for robusta.
The graph suggests some interesting patterns. First, except for 2 of the past 430 months, the price of arabica has always been above the price of robusta. Second, the gap between the two prices seems to be widening since 1986, suggesting that consumers are increasingly appreciating quality. Third, there are fluctuations in both prices but those fluctuations are more remarkable for arabica. Indeed, arabica coffee prices are quite spiky. In the past three of those spikes, arabica coffee prices reached more than double the price of robusta coffee. This blog post does not have the grounds to determine whether those spikes have been driven by supply disruptions or other factors.
How this graph was created: Use FRED’s keyword search method to find the two series: “coffee robusta” leads you to the series ID PCOFFROBUSDM and “coffee arabica” leads you to the series ID PCOFFOTMUSDM. Each series is the monthly price of the coffee in US$ per 100 lbs.
Suggested by Alexander Monge-Naranjo.