How do I update all records by entering value in a field?

[TomNick]

Hi,

I would like to update all the records in a database by entering a
percentage value in a form.

The condo owners in the building where I live have monthly fees to pay. From
time to time, these fees have to be increased. I would like to be able to
enter a percentage value in a form, and have all the records be updated by
that value (ex.: monthly fees $100 + 10% increase = new fee $110).

Thanks.

Tom.