Last year, the Transportation Security Administration (TSA) discovered a whopping 3,391 firearms in carry-on bags across the country – and it looks like 2017 is on track to breaking that record.

Based on the TSA blog’s “Week in Review” posts, so far over 2,000 firearms have been discovered in carry-on bags this year. And, just last month, between July 24th and July 31st, a new record was set for the number of firearms discoveries in a single week: 96.

While these numbers seem high, they aren’t exactly surprising. The number of firearm discoveries at TSA checkpoints has steadily increased over the past decade. This can likely be attributed to the fact that the number of people traveling in the U.S. has also gone up. In 2016, more than 738 million passengers were screened by the TSA; that’s over 43 million more than in 2015. This year, that number is expected to be even higher.

It’s important to note that the number of concealed carry permits – and gun sales – has also increased over the years. So, it’s safe to assume that not only are more people traveling, but more people with guns are traveling.

In fact, some of these cases of firearm discoveries involve gun owners who simply forgot what they were carrying when they went to the airport. It sounds like a weak excuse – if you’re a responsible gun owner, you should know where your firearms are at all times – but it does happen. Unfortunately, we don’t know exactly how often this scenario takes place, since the TSA provides no breakdown of its numbers.

Perhaps the agency should start tracking how many of these guns belong to permit holders and how many are illegally owned. It would also be helpful to know how many of these firearms are discovered in actual carry-on suitcases and how many are found in purses or on the passengers themselves (common places CCW permit holders carry their guns).

Regardless, if you are planning on traveling with your firearm, please know the rules. Guns are allowed on planes, but only in checked baggage. You must also be sure to declare the gun at the ticket counter, and the gun must be unloaded and stored in a hard-shell lock box, separately from ammunition.