When the end of the working week arrives, it can be a little harder to keep going. If you work from Monday to Friday, you might find yourself thinking about the weekend as your brain and body get ready to rest. You may feel that you're getting less work done. You might even feel this way near the end of each work day. And a study from the US has found that yes, it's true — we aren't as productive and we make more mistakes in the afternoons, especially on Fridays. While most of us could probably have guessed that result, the researchers said most studies in the past have just asked workers about their feelings related to their productivity. But this one actually used data based on computer use, including how fast people typed and the numbers of typos they made. The researchers, from Texas A&M University, looked at the computer use of 789 employees working from the office of a big company in Texas. They studied them for two years and looked at their computer use at different times of the day and week. And they found that computer use "dropped significantly" on Fridays. One of the researchers, Taehyun Roh, said: "Employees were less active in the afternoons, and made more typos in the afternoons — especially on Fridays." The authors added that results like this should encourage bosses to think about flexible working arrangements or four-day working weeks to get the best from their employees.