You can create a new version of spreadsheets to track and record important changes made to them.
To create a new version of the document, select File > Create new version from the Command menu. In the opened dialog window, specify the name of the new version of the file and click OK. This will create a new version of the file with the specified name.
You can view and edit the created version (and earlier versions) in the Version history of each document, which can be found in the MyOffice Documents application.