Detailed Instructions: This task is about writing a correct answer for the reading comprehension task. Based on the information provided in a given passage, you should identify the shortest continuous text span from the passage that serves as an answer to the given question. Avoid answers that are incorrect or provides incomplete justification for the question.
Q: Passage: Cyprus suffers from a chronic shortage of water. The country relies heavily on rain to provide household water, but in the past 30 years average yearly precipitation has decreased. Between 2001 and 2004, exceptionally heavy annual rainfall pushed water reserves up, with supply exceeding demand, allowing total storage in the island's reservoirs to rise to an all-time high by the start of 2005. However, since then demand has increased annually a result of local population growth, foreigners moving to Cyprus and the number of visiting tourists while supply has fallen as a result of more frequent droughts. Question: Why has the water supply shrunk in previous years?
A:
more frequent droughts