Instructions if your mouse was not recalibrated for the new year.
You should actually do this every year. Even more often is recommended by Kim Kommando (the computer guru) if you spend a lot of time on the computer. I was shocked to see how well this works!
To re-calibrate your mouse, click and hold on the Y below. Then drag the Y toward the g. If it doesn't work immediately, you might want to clean your mouse.