I want to know the answer to the following question:
How much money has been generated due to the Duck Stamp act?
All the background I'm provided with is that "Since 1934, the sale of Federal Duck Stamps has generated $670 million, and helped to purchase or lease 5,200,000 acres (8,100 sq mi; 21,000 km2) of habitat.". Is that enough to answer the question?
Answer: yes