Recreational marijuana sales began in Washington State in July 2014. At first there were supply shortages, high prices, and not that many stores. There are still not that many stores compared to how many there will eventually be, but supplies are abundant and as a result prices have dropped. The numbers are out for 2014, and one marijuana store stood above the rest when it came to overall sales. One would likely think that a store in Seattle would have sold the most marijuana, however, that's not the case. Per Marijuana Business Daily:
The highest-grossing retail marijuana shop in Washington State is located just a few miles from the border with Oregon, which is in the process of setting up its own recreational cannabis industry.
The New Vansterdam retail store - in Vancouver, Washington - recorded $3.2 million sales from the start of legalized rec in July through the end of 2014. The shop is just minutes from Portland, Oregon, which has a population of more than 600,000 residents.
Its sales outpaced Cannabis City in Seattle, which generated $3.19 million, the Seattle Post-Intelligencer reported, citing data from the Washington State.
I'd expect the sales numbers to stay strong along the Oregon border for about another six months, but then they will slowly decrease as Oregon implements it's own marijuana legalization law. At first more and more Oregonians will grow their own marijuana (something that Washington residents aren't allowed to do). Then eventually stores will open in Oregon, and people won't be crossing the border to buy marijuana anymore, as Oregon marijuana prices are going to be significantly lower than Washington's due to a much lower tax rate on products.