Today marks the last day American flags will fly at half-staff to honor former President George H.W. Bush, who passed away Nov. 30.

The lowered flag is a symbol of national mourning that occurs after certain tragedies or the deaths of public dignitaries as well as days of remembrance. In 2018, the flag stood at half-staff after school shootings in Parkland, Florida, and Santa Fe, Texas, as well as after the deaths of former First Lady Barbara Bush, U.S. Sen. John McCain and Reverend Billy Graham. And those are just a few examples.

There have been no shortage of tragedies in recent years. An analysis by The Nevada Independent found that American and state flags were flying at half-staff for 8 percent of 2015, 18 percent of 2016 and 7 percent of 2017, based on executive orders issued by Gov. Brian Sandoval.

As we prepare to raise the flags again tomorrow, here’s a video explaining the many reasons they can be ordered to half-staff and how often that generally occurs — just enough information to make that somber symbol a bit more meaningful when you see a lowered flag flapping in the wind.