The account's Activity tab performs a mock close at the beginning of a fiscal year, but does not mock close the net surplus/deficit during the fiscal year. If there is a net surplus/deficit during the fiscal year, then the ending balance of one fiscal year will not match the beginning balance of the next fiscal year.
A fund balance account's Activity tab for period 12 of 2003 with a beginning balance of $100.00 shows an ending balance of $100.00.
Assuming a net surplus/deficit of $250 for 2003, that fund balance account's Activity tab for period 1 of 2004 shows a beginning balance of $350.00, which includes the net surplus/deficit of $250.00 from 2003.
The General Ledger report and other Financial Statements perform a mock close, rolling net surplus/deficit information to their respective fund balance accounts. This can result in a different balance on the report than the detail on the account Activity tab, depending on the fiscal period for which the activity is being viewed.