In the swirl of anguish and uncertainty that followed the devastating floods in Central Texas, one of the most confounding elements of the aftermath was why there were so many people still missing weeks after the disaster. Where were they? Who were they? What happened to them?

Last week, state and local officials said there were 97 people missing in Kerr County, which sustained the worst of the July 4 floods in the Hill Country. But then, on Saturday, they released a revised figure: three. The death toll there remained unchanged; the county had 107 of the 135 deaths recorded statewide.

The drop was substantial, yet it was not entirely unexpected, according to officials and those familiar with the rhythms of deadly natural disasters.

The fluctuation was a reflection of the chaos unleashed by a disaster of this magnitude and of the methodical work — sometimes painstaking to the point of frustration — required to bring clarity to the confusion. Whether in flash floods, wildfires or tornadoes, making sense of the list of the missing is a crucial part of the official response.