Calculations should not be stored in tables. Calculations are performed in queries and forms. Relational databases are not spreadsheets and should not be confused with them even if the tables do resemble spreadsheets. All data can be retrieved in a query as needed and therefore you would not save it in a table. If the data changes, then you would be constantly updating the tables. This is contrary to database principles. If you need the data printed, make a report, export the query to excel or just simply print the query.
Here is some information on building relational databases and an explanation on the differences between excel and access.
http://forums.aspfree.com/microsoft-...es-208217.html
http://forums.aspfree.com/microsoft-...el-349267.html
Take a few minutes to read them. It will help you in your designing.