o ∆ in GDP 1 period —> next gives indication of econ growth
o ↑ GDP —> expansion —> smooth pattern (otherwise overheats)
• Upward movement on business cycle
•
o ↓ GDP —> contraction
• Decrease in business cycle
• Sometimes needed
Measuring GDP
• ABS calculated GDP
o Chain Volume Management – prices from different g & s tend to grow at different rates.
• Therefore the base year’s price info is irrelevant when it is far from actual yr
▪ ABS calculated GDP slightly diff than using base period price → real econs much more
complicated!!
• We need to get A of the quantities of many goods —> 1 number
• Not all g&s can be bought & sold in markets & therefore excluded from the GDP measurement
o Eg. Plumber fixing himself
o Eg. Childcare and home production – we can’t put a value on it
o Eg. Public goods like public defence don’t have a value
• To do with market value (prices used)
• Only looks at the final g&s produced —> otherwise you’d be double counting
o Don’t include all goods in production process – it’s the final
o Eg. Grain & flour = intermediate goods. Bread is the final good
• Hard to differentiate between intermediate goods or not
▪ To deal with this, economics will determine the final value of the good indirectly
• Sum up all the intermediate goods —> value added approach
• Value added by any firm = represent the portion of the value of g&s
that each firm created in its stage of production
• Summing up gives same value
• Market value of product – costs of inputs from other firms
o Only g&s produced within one country —> Domestic
Types of methods to calculate GDP
1. Value Added (Producction) Method