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:
IPod

Context:
On January 22, 2008, Apple reported the best quarter revenue and earnings in Apple's history so far. Apple posted record revenue of US$9.6 billion and record net quarterly profit of US$1.58 billion. 42% of Apple's revenue for the First fiscal quarter of 2008 came from iPod sales, followed by 21% from notebook sales and 16% from desktop sales.

Question:
How much of Apple's revenue resulted from purchases of laptop computers in Q1 2008?

21%