On Czech websites they say almost 4 million cars including 1 million Skoda, here German source:

"According to information from the Federal Motor Transport Authority, the Volkswagen brand accounts for more than two million vehicles worldwide. Skoda has more than one million vehicles, Audi around 700,000 and Seat around 200,000, according to informed sources."

https://www.handelsblatt.com/unternehmen/industrie/volkswage...