In class, we were given a set of data which we formatted into a data table. We were instructed to extract data using a number of different criterion. Some of the values were numerical, such as age, sales, etc. and other values were letters which represented sex, District, etc.

I had difficulty with one of the sets of criterion: Select records that represent Division D and District 2. When I typed D into the criterion field, the "D" data would not extract from the data set. I had no issues with any other data. Finally, I copied and pasted the D from the data set into the criterion field and it worked.

I am wondering what would have caused this anomaly. The data set came from Cengage.