The property taxes that you pay are used for a number of things such as road construction, the police and fire department, and organized recreation in your area.
The increase in the trade of silver during the period between 1550 and 1800 is due to the fact that silver was started to be used as a standard currency for trade purposes. Even though it was not considered as "legal tender", as it would later be used for this purpose with the introduction "Bimetallism" in the 19th century, it was widely adopted as a tool for trade among the civilizations that existed at the time.
Your answer is Navigation Acts. Hope this helps! <span />