Open any Data table view, e.g. Projects > Budgets.
There is an Export icon next to the filters on top of the screen.
You will find the same button on all of the data table views in Productive such as:
Billing > Invoices
Tasks > Layout in Table view
Company time > Layout in Table view
etc.
Clicking the Export button will allow you to choose between several formats.
What you see is what you get, so make sure that the right view is selected before exporting your data.
You can also customize and save views after changing them, so that you always export the same format of the table, with updated information.