Sure. Your file is either used a lot or has been used for a long time.
Go to the first completely blank column to the right of your data and select it by clicking on its column letter.
Now, hold Shift+Ctrl and hit the right arrow key once. Let go of the keys. From the menu, hit Edit-Clear-All.
Go to the first completely blank row at the bottom of your data and click on its row number.
Now, hold Shift+Ctrl and hit the down arrow key once. Let go of the keys. From the menu, hit Edit-Clear-All.
Save the file.
All done!