On March 14th, 2012 (3/14/2012), it was Pi day. According to Wikipedia, Pi (π) is a mathematical constant that is the ratio of any Euclidean circle’s circumference to its diameter. While others estimated π using Monte Carlo in R or declared π is wrong, I tried to see how many times the pi value is cited in Pubmed, a database of references and abstracts on life sciences and biomedical topics. And here are the results (please note the log y-axis):

I know it has little meaning: very often the string of numbers in the pi value was not there for pi itself but for other reasons. I thought it was fun, that’s all.