One of the most important question types on the quantitative section of the GRE is Data Interpretation, which is sometimes referred to as Data Analysis. Unlike, say, the algebra and geometry questions, Data Interpretation questions don’t rely so much on your knowledge of mathematical formulae. Rather, they primarily test your ability to make sense of numerical information that’s presented graphically, usually in the form of some kind of graph or chart.
While the actual mathematical concepts are not always as challenging as other GRE quant question types, Data Interpretation questions can be surprisingly tricky. And it’s important to learn how to work with them, since they account for approximately 20% of your GRE quant score. In this section, we’ve collected several tips and strategies for you to consider as you go about your GRE prep.
1. Get familiar with graphs and charts
The main thing that makes Data Interpretation questions unique is that they all involve your ability to encounter graphically/visually arranged numerical information, to understand it, and to accurately calculate required values based on the information. For some people, reading graphs and charts comes naturally. For others, it’s like reading a foreign language.
You should familiarize yourself with the main forms of graphic data you’re likely to encounter on GRE Data Interpretation question: bar graphs, line graphs, pie/circle graphs, scatter plots, and numerical tables. Some DI questions even combine multiple kinds of graphs. Working with official GRE practice tests is an excellent way to familiarize yourself with these kinds of figures. You can also practice by reading periodicals that deal with numerical information represented visually, such as The Economist and the Business section of the New York Times.
2. Lock down the necessary math skills
While the math skills required for Data Interpretation questions aren’t as challenging or complex as the other GRE Quant questions, you want to make sure you’ve mastered the skills you do need to know, so you don’t waste time. The primary math concepts involved in Data Interpretation questions include fractions, percentages, ratios, decimals, probability, and statistics.
3. Be patient and thorough
Data Interpretation questions require more time than other GRE Quant questions. You should allow yourself roughly 2 minutes per question for Data Interpretation. Use this time not only for your calculations, but to make sure you’ve fully understood the question and the information.
4. Read the question carefully
Data Interpretation questions often contain at least one answer that seems right, but isn’t. This is to test your ability to read closely and accurately. Make sure you’ve actually understood what the question is asking. Some questions are designed to trick you. For instance, a question may ask whether Company 1 or Company 2 has experienced a greater percent increase in revenue. Company 1 may have experienced a greater increase in revenue by total dollar amount, but not by percentage.
5. Don’t be afraid to approximate
Another way you can save yourself time and complexity on Data Interpretation questions is knowing when to round/approximate. If the answer choices are all quite different from one another—for instance 0.104%, 1.04%, 10.4%, and 104%—you can round these figures to 0.1%, 1%, 10%, and 100% for the sake of speed and simplicity.
You also need to know when not to round. If the answer choices are 9.6%, 10%, 10.4%, and 10.8%, you’ll need to maintain the decimals.
6. Use your eyes wisely
One of the benefits of representing information visually is that it can help you arrive at a more intuitive sense of what’s being presented. If you’re having trouble with the numerical calculations, you might be able to formulate a reasonable guess based on just looking at the information. For example, one bar may seem to be roughly 50% greater than another, allowing you to approximate a 50% increase from the first to the second.
7. Know when to move on
Just because you have a bit more time for Data Interpretation questions doesn’t mean your time is infinite. One mistake people often make is getting so bogged down in their calculations, they forget to keep track of time. If a question is taking more time than you have to answer it, there’s a good chance you won’t arrive at an answer with certainty anyway. In cases such as these, make your best reasonable guess and move on.
8. Don’t do more than you need to
Another mistake people make a lot on Data Interpretation questions is doing more work than they need to. For example, a graph may depict yearly changes in revenue for four different companies, and a question may ask about which of two companies experienced a greater total decrease in revenue from one year to another. Some students will make the mistake of calculating the decrease in revenue for every company, every year, or both.
9. Work with a tutor
The best thing you can do for your GRE Data Interpretation prep is work one-on-one with a tutor. A qualified tutor will be able to help you improve your skills not only at Data Interpretation, but at every aspect of the GRE. They’ll work with you to design a personally tailored study plan that will maximize your score, and they’ll also share specialized tips and tricks to target your specific strengths and weaknesses.
Just because the math is technically simpler for GRE Data Interpretation questions doesn’t mean they’re easier than other GRE Quant questions. Data Interpretation questions contain their own specific challenges and pitfalls, and you’ll want to devote extensive time to learning what these are. If you focus on these tips and strategies as you prep for the GRE, you’ll be prepared to handle any Data Interpretation question you come across.