How many people in the Netherlands can speak English?
Although I am pleased with all the complimentary comments and percentages, I have to put a note to it. While most Dutch do speak English, many do speak it less than perfect. Good enough to chat with a tourist, but not good enough to represent a company in an meeting with native speakers. Most Dutch learn to speak informal English, but nearly non can speak formal English with someone with a higher status, even worse, most Dutch are not even aware that you need to adjust your English in that case. So yes, more than 50% of the Dutch speak English good enough not to be embarrest speaking it with you, but only a few percent will speak it good enough not to embarres you when they represent you at a business meeting with important English speakers.