This FAQ entry will show you how to modify tax rates in timeSensor LEGAL, should that become necessary.
Go to "Special", then choose "Tax Rates" in the "Accounting" menu.
Double-click the current tax rate and choose "Change Tax Rates" in the "Tools" menu.
In the next window, enter the new tax rate, its start date and a new code.
Save your changes by clicking OK and that's it.
Invoices with a creation date prior to the validity of the new tax rate will use the old rate. Invoices with a creation date after the validity of the new tax rate will use the new rate.
Please note that the date of the service is irrelevant. If you've provided services under the old tax rate, but invoice them in the new tax rate period, the invoice will use the new tax rate. If you wish to invoice services provided before the change under the old tax rate, you must create an interim invoice.