Answer 1 = About 1.8 Million
Answer 2 = depends just about 1000 to 1500 people each day
Answer 3 = depends could vary between 500 to 1000 people
Answer 4 = Average car's per family = 2, which means there are forsure over a Million Vehicles with New coming on the roads each days and lots more going to the garage / scrap each day.

These are my statistics based on my observation