As the summer draws to a close, so too does BBQ season. With this in mind, this week's viz takes a look at trends in BBQ shipments (sales) over the past three decades in North America.

Viewed over the entirety of the 1985 to 2013 period for which data are available, the BBQ market--including charcoal, gas, and electric units--demonstrated seemingly healthy growth, with shipments increasing by 25% over 28 years. That said, as with most other consumer product markets, the period was characterized by ups and downs, with the total number of shipments actually peaking in 2008 at 17.4 million units. The number of shipments dropped sharply during the recession in 2009 and then continued to slide from there, sinking to 13.9 million in 2013.

When shipments are adjusted for population, a different perspective emerges, with the annual number of BBQ shipments per 1,000 people in North America actually falling between 1995 and 2013--from 42 to 40. More marked was the drop in per capita BBQ shipments since the mid-2000s, having fallen by 23 percent from 52 shipments per 1,000 people in 2006.

Why the recent decline in BBQ shipments, or the longer-term decline in the per capita rate? it could be the result of many factors, ranging from the rising cost of meat to BBQ market saturation. If it's the latter, we trust you already own a BBQ--so don't forget to take advantage of last remnants of BBQ season.