1. The VAT liability ratio (90%)
Payroll tax is due where receipts carrying a right to deduct VAT represent less than 90% of total receipts for the preceding year (and not of "taxable turnover" in the accounting sense). This liability ratio determines the base of the payroll tax: if the ratio is 70%, payroll tax applies to 30% of remuneration. The 10% rule is a tolerance for activities that almost entirely carry a right to deduct. It is essential to distinguish operations outside the scope of VAT (which carry no right to deduct) from operations exempt within the scope (which are in principle treated as operations carrying no right to deduct, subject to a limited list of exceptions).