My dad is the crossword champion of our family – it’s rare that he can’t polish off the Saturday puzzle. I, on the other hand, am usually googling (i.e., cheating) by Wednesday. I’m just more of a KenKen guy.

After creating the chess square utilization graphic last week, I realized it might be interesting to run a similar analysis on crossword puzzle grids. I pulled the grids of just over 7400 crosswords from The New York Times – the database included all Will Shortz-era puzzles, starting November 21, 1993 through March 10, 2014. I then removed grids with non-standard dimensions. Standard for Monday to Saturday is 15x15. The majority of Sunday puzzles are 21x21; while there are some 23x23, they account for less than 10% of the Sunday puzzles.

I then calculated, separately for each day of the week, how often each box was a blank (black shaded square) versus a box with a character (part of a solution). I’ve used the word “character” because, though the entry is almost always an individual letter, it can sometimes be something tricky like a number or multiple letters.

The percentage shown after the day of the week represents the average percentage of boxes for that day that requires characters. So, as the week goes by, the puzzles have fewer and fewer black boxes and more white boxes needing answers.

The shading scale ranges from 40% to 100%; the former indicates that a box contains a character (i.e., is not shaded black) in 40% of puzzles on that day of the week, while the latter specifies that a box has always required a character. The actual lowest value for any puzzle is 39.8%, which appears as black squares in two locations on Monday. All values for individual boxes are written in blue.

Note the striking similarity between Monday through Thursday puzzles, with Monday having the most contrast and Thursday, the least. Friday and Saturday appear similar and have comparable percentages, while the larger Sunday grid is in a league of its own. I’ve also provided the average of the Monday through Saturday puzzles. This allows you to see which boxes have never been black on a non-Sunday puzzle.

Data source: http://www.xwordinfo.com/ (If you’ve never seen this site, check it out – they have some amazing statistics on the NYTimes Crossword!)