Another factor is the age of the resort. After a resort sells out and a developer is no longer there pushing exchanging, a much larger percentage of resales tend to go to own-to-use buyers than during the developer sales phase, so over time the percentage of exchangers tends to decline.
My first office when I served on my HOA board at a sold out resort on the NC Outer Banks was as First VP, and part of my portfolio was reselling HOA owned weeks. I did a lot of research to get a handle on trends at the resort, and found that there were some clear patterns, with by far the fewest exchange deposits in the prime summer, about 10%, and the most in the deepest offseason, but generally averaged only about 30% of weeks even in deep offseason. Spring had the same percentage of exchange deposits as off season, but the Fall fishing season was only about 20% exchange deposits. In talking with resort managers at some other resorts, none of them had sat down and counted, but they also said they estimated something under 30% for exchange deposits overall, with significantly less in summer and somewhat less in Fall, so essentially the same pattern.
This also gave me an interest in ''talking shop'' with resort managers when I was on an exchange. I have had some resort managers in the UK give estimates fairly close to the Outer Banks numbers, but in France and Germany, I had a couple of resort managers tell me that the percentage of weeks at their resorts that went to exchange companies was in the single digits.
One UK resort manager told me that since members had started seeing their exchange options at RCI decline, some had switched to independent exchange companies but for those who did not want to do that, the HOA had set up a rental program where they handled rentals at the resort on behalf of members, something they had not been doing until they started getting complaints that RCI was not working for members the way it had before. Those weeks going into the resort's new rental program also cut down on the number going to exchange.
Of course, these are all resorts that are long sold out. Managers at resorts still in sales are much harder to talk to on such things.