As the tally of states that have legalized adult recreational or medical cannabis use increases, it's becoming easier than ever for consumers – particularly the law-abiding kind – to get their ganja. Still, an ounce can set you back a pretty penny in some areas: D.C.'s $595.69 average price is nearly triple that of Oregon, for example. To get a clearer picture of how prices vary across the country, we've put together a reference using Price of Weed data, which compiles anonymous submissions from buyers:

One of the first trends to stand out in the map above is how cheap pot is in recreational markets, particularly Washington state, Oregon and Colorado, all three of which allow retail sales. Alaska, the nation's 11th-cheapest market, legalized recreational use in February 2015 and opened its first dispensary in October 2016.

Puzzlingly, the functionally decriminalized D.C. market is the nation's most expensive by far. According to a Forbes story using Price of Weed data, the price – which was just $346 in May 2015 – jumped to $538.92 in September and $595.69 as of Friday. According to a knowledgeable source Investopedia consulted on Friday, the Price of Weed data is probably inaccurate: "That's not my experience at all," the person said, estimating the average black market price in D.C. at $300 to $350. 

More Legal Markets on the Way?

California, Maine, Massachusetts and Nevada voted to legalize recreational use through ballot measures in November. Arizona voted its measure down. 

More state governments may find themselves tempted by the tax hauls legal-market states have summoned, basically ex nihilo, while eliminating a whole swath of resource-draining petty crime. Colorado, for example, brought in more than $88 million in the year to May 31, 3015 – up from $25 million the previous year – compared to $49 million in alcohol tax revenues. Oregon is expecting to take in over $44 million in calendar 2016. Washington made $40 million in the year to June 30, 2016 and $21 million the previous year. (See also, Legal Weed Market to Triple in 5 Years.)

Those amounts hardly make a difference to the states' overall budgets – Washington's is $38.2 billion for the 2015-2017 biennium – but there aren't many other products you can slap with excise tax rates of nearly 29% without causing a fuss. After all, for now at least, the Coloradans who pay that tax know that just across the border in Kansas, an ounce costs an extra $100.

The good times may come to an end, however. The leniency with which the federal government – which still prohibits marijuana possession and use – has treated state markets is largely a product of the Obama administration's policies. On Thursday, Donald Trump's press secretary Sean Spicer said that "you'll see greater enforcement" of federal drug laws, singling out recreational use as "very different" from medical use. Attorney General Jeff Sessions has long opposed drug legalization, telling Congress in 2015, "Good people don't smoke marijuana." He may reverse his predecessor's laissez-faire approach to the devil's lettuce, which could potentially undermine state legalization.

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