The ACT has announced that at some point during the 2021-2022 school year, students may have an additional question type on the ACT Reading section: Visual Quantitative Information questions. These questions will most likely be found on one of the three Informational Reading passages, as opposed to a fiction passage.
What will these questions be like? Check out this link for some sample visual quantitative information questions. Unfortunately, until tests that have these questions are released, these appear to be the only official sample questions ACT has made available.
Why is the ACT adding this question type to the reading section? Most likely it is because the SAT has done so on the Evidence-Based Reading and Writing section, and the ACT would like to assess similar skills. This is yet another example of how the ACT and SAT tests have increasingly converged in recent years, making it easy for students to transition from one test to the other.
So, what should students who are concerned about these new question types do to prepare? First, go into the ACT reading section with a flexible mindset; if you come across a series of graph analysis questions, know that they will only test you on the information in the reading passage and the graph. No outside knowledge will be required. Second, practice with some SAT reading passages that have graph analysis questions. Each SAT reading section has about 4-5 questions of this type, so you will have far more to work with than the limited sample ACT has provided. Here is a link to several SAT practice tests that you can review.
Best of luck!