6. Question 5: The number of people living in the city centre declined sharply.
7. Question 6: There was a sharply decline in the amount of land available for building.
8. Question 7: During the period 1970 to 1995 number of people travelling abroad increased gradually, but then fell sharply in 1996.
9. Question 8: Sales of computers rose dramatically from just under 1 million per year to over 3 million per year between 1995 and 2005.
10. Question 9: There was a steady decline of sales of houses between 2006 and 2008, but then sales increased slightly in 2009.
11. Question 10: The percentage of people who got married in the USA slight declined in the 1990s but rose again in the 5 year period from 2000 to 2005.