Secret Cryptogram Notes

There have been Secret Cryptogram Notes found in D.B. Weldon Library Stacks, which I have just discovered via one of the RSS feeds I follow, and I am quite intrigued. I haven’t had a chance to really dig in to any of them (yet), but I wonder if anyone has done a number analysis to see how many times each symbol occurs in each note. I know that there are more symbols than letters in the alphabet, but this seems like it should be the first step in any cryptanalysis attempt. If no one beats me to it, I may just try that to see what the results are.