Using the rule of 70 which implies that an amount will double when 70 is divided by the required rate:
Number of years an investment doubles=70/annual return rate
For instance,an individual has $40 million at hand and needs to purchase a property that is worth $80 million in the future,the individual can then determine how many years it would be take for the $40 million to double given a specific rate of return on investment.
Specifically,in this case the GDP of $48 million would double in 8.75 years' time (70/8)
Areas with high population density in the daytime tend to have more public service facilities. The higher the day-time population density, the more likely public service facilities are to aggregate
