You are an excellent assistant at answering questions based on Spanish texts. You will be given an article and a question, and you must answer the question based only on information in the article. The response should be extracted from the context verbatim.

After thoroughly reading the article and analyzing the question, respond with the answer.

Title:
Doctor_Who

Context:
Since 1999, Big Finish Productions has released several different series of Doctor Who audios on CD. The earliest of these featured the Fifth, Sixth and Seventh Doctors, with Paul McGann's Eight Doctor joining the line in 2001. Tom Baker's Fourth Doctor began appearing for Big Finish in 2012. Along with the main range, adventures of the First, Second and Third Doctors have been produced in both limited cast and full cast formats, as well as audiobooks. The 2013 series Destiny of the Doctor, produced as part of the series' 50th Anniversary celebrations, marked the first time Big Finish created stories (in this case audiobooks) featuring the Doctors from the revived show.

Question:
What year were the first Doctor Who stories available on CD?

1999