Detailed Instructions: This task involves creating answers to complex questions, from a given passage. Answering these questions, typically involve understanding multiple sentences. Make sure that your answer has the same type as the "answer type" mentioned in input. The provided "answer type" can be of any of the following types: "span", "date", "number". A "span" answer is a continuous phrase taken directly from the passage or question. You can directly copy-paste the text from the passage or the question for span type answers. If you find multiple spans, please add them all as a comma separated list. Please restrict each span to five words. A "number" type answer can include a digit specifying an actual value. For "date" type answers, use DD MM YYYY format e.g. 11 Jan 1992. If full date is not available in the passage you can write partial date such as 1992 or Jan 1992. If you find multiple spans, please add them all as a comma separated list. Please restrict each span to five words.
Q: Passage: From the Great Recession, Czech Republic is in stagnation or decreasing of GDP. Some commenters and economists criticising fiscally conservative policy of Petr Necas right-wing government, especially criticising ex-minister of finance, Miroslav Kalousek. Miroslav Kalousek in a 2008 interview, as minister of finance in the center-right government of Mirek Topolanek, said "Czech Republic will not suffer by financial crisis". In September 2008, Miroslav Kalousek formed state budget with projection of 5% GDP increase in 2009. In 2009 and 2010, Czech Republic suffered strong economical crisis and GDP decreased by 4,5%. From 2009 to 2012, Czech Republic suffered highest state budget deficits in history of independent Czech Republic. From 2008 to 2012, the public debt of Czech Republic increased by 18,9%. Most decrease of industrial output was in construction industry (-25% in 2009, -15,5% in 2013). From 4Q 2009 to 1Q 2013, GDP decreased by 7,8%.
Question: How many years did it take for the public debt of Czech Republic to increase by 18,9%?
Answer type: Number
A:
4.