Although it is not required for our system, many will store a backup tonight that has their financial data for this year. They never know when this might be required.
I do not do this what I do is run my financial reports and store them by emailing my personal accounts these reports.
These reports will be
4) Payroll reports.
Then I archive them in my personal email account where they will sit there for years just in case. You never know when you need them.