I’ve struggled with recent 15x15 puzzles. I used to make a point of solving these within a day or two at the latest, but recently I’ve found myself racing against time to get them completed before they disappear. I failed to complete the ones published in April and I’ve just managed to complete the May 13th puzzle a few minutes ago. Prior to that, the last time I solved a 15x15 was on April 10th - more than two months ago.

I’d love to know if there are any stats regarding how many people on average manage to solve each 15x15 and whether these stats reveal a downwards trend. I’d also like to be able to see the solutions to the ones that I haven’t managed to solve, but the puzzle just disappears when it’s out of time. Maybe it could be left up for an extra day after it no longer becomes eligible for points?

Below is a quick plot of the number of times the 15x15 was solved since January 2022.

The last 3 bars can still go up of course. I don't really see a downward trend..

(edit: the average of all except the last three is 92, standard deviation 8.6, so the odd one out recently
was April 29th, with only 69 solvers).

Thanks Patrick.

It’s probably just me so. I’ve been spending a bit less time on the site and not stressing out as much as I used to about doing all the daily puzzles. Hopefully it’s not a sign that I’m starting to lose my cognitive reasoning power.

Patrick, thanks for sharing the info.

Paul, I have not noticed a significant increase in difficultly in the 15 x 15. Occasionally, there is one that doesn't POP for me, but that usually is a mistake on my part.