Passage: The film has earned $599,045,960 worldwide. Casino Royale was the 4th highest-grossing film of 2006, and was the highest-grossing instalment of the James Bond series until Skyfall surpassed it in November 2012.Upon its release in the United Kingdom Casino Royale broke series records on both opening day—£1.7 million—and opening weekend—£13,370,969. At the end of its box office run, the film had grossed £55.4 million, making it the most successful film of the year in the UK, and as of 2011, the tenth highest-grossing film of all time in the country.On its US opening day Casino Royale was on top with $14,741,135, and throughout the weekend grossed a total of $40,833,156, placing it second in the ranking behind Happy Feet ($41.5 million). However, Casino Royale was playing in 370 fewer cinemas and had a better average ($11,890 per cinema, against $10,918 for Happy Feet). It earned $167,445,960 by the end of its run in North America, marking what was at the time the highest-grossing film of the series, before being surpassed by Quantum of Solace's $168.4 million.On 18 November 2006 Casino Royale opened at the first position in 27 countries, with a weekend gross of $43,407,886 in the non-UK, Irish, US or Canada markets. The film retained the top spot at the worldwide box office for four weeks.

Question: How many 7-day periods was the movie at the top spot?
four