This started in the W&D thread, moving it to it's own thread to avoid totally dumping on that one. @Texas84 was suggesting that the addition of the 10k race is what was causing the registrations for the halfs to drop. And was threatening to post numbers if the time/motivation arose. So consider this your motivation. ; ) @LAKid53 said we should be able to just look at the finisher counts to see. And below follows my thoughts Except that the results just show finishers. Doesn't show people who failed to finish for whatever reason, nor does it break down the challenge vs non challenge. Last time I checked, the challenge runners were only reflected in a PDF, and not broken out in the individual race totals. And of the challenge runners, there is no break down on those who ended up only completing one or the other for whatever reason. (Yeah, I'm being nitpicky about actual vs approx, but when I do demographics for events stuff like that matters) But ok, lets compare 2016 and 2017 Tink. (Chosen since its the default on the results tab) 2016 had 8,369 10k finishers, 2017 has 8,623 finishers. 2016 had 13,144 half, 2017 had 10,799 half finishers. 2016 had 94 pages of challenge racers, 2017 has 98 pages (with approx 45 per page). So I think we can assume that the number of challenge runners were a wash, but 2,345 more people finished the half in 2016 than in 2017, while only 300 more people finished the 10k in 2017. And of those 300, almost 200 were challenge runners. So thats 2,000 more total participants in 2016 than in 2017, all of which had done the half. Now admittedly Tink had a 10k from the start, but each year (except for 2017) there were just about 13,000ish half finishers, and about 8,400 10k finishers. 2017 had a huge drop. DLR (Year, 10k, half finishers) 2013 7,839 15,872 2014 9,608 15,979 2015 9,049 15,248 2016 9,006 13,084 Now not knowing registration numbers, I would still believe that from 2013-2014 they added approx 1,800 slots. But no corresponding drop in the half. But last year, with no apparent increase to the 10k, 2,164 less people finished the half. Now those are both West Coast races, and neither set of data contains any numbers from non-10k weekends (Tink because it doesn't exist, and DLR because I'm lazy and it's not on trackshackresults at the same place as those years). So please, if anyone else has the data from the races, as well as other years handy, please post them for all to see. My posted data is a small subset and could easily have been selected to show one side (although it wasn't, it was just handy) so I'd love to see more to help further discussion and thoughts. More data is always good data.