What exactly does “divorce rate” refer to? The term “rate” suggests a relationship to time (the the number of occurrences over a specific amount of time as in per year, per month, etc. So, an increase in the “rate” of divorce would mean there are more divorces over the same time period than in earlier surveys.
That’s not the same thing as there being more cases of divorce among certain segments of the population than others. It could even theoretically include a revelation that more divorces take place during one season of the year than in another, no?