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:
Comcast

Context:
The book value of the company nearly doubled from $8.19 a share in 1999 to $15 a share in 2009. Revenues grew sixfold from 1999's $6 billion to almost $36 billion in 2009. Net profit margin rose from 4.2% in 1999 to 8.4% in 2009, with operating margins improving 31 percent and return on equity doubling to 6.7 percent in the same time span. Between 1999 and 2009, return on capital nearly tripled to 7 percent. Comcast reported first quarter 2012 profit increases of 30% due to increase in high-speed internet customers. In February 2014, Comcast generated 1.1 billion in revenue during the first quarter due to the Sochi Olympics,.

Question:
What was Comcast's share value in 2009?

$15