ECON Lecture 9 Notes: Gross Domestic Product (GDP)

Market Transactions: Three Equivalent Aspects

  • Every market transaction involves three equivalent aspects:
    • Product/Service Value: Determined by agreement between buyer and seller.
    • Buyer's Perspective: Expenditure/Cost.
    • Seller's Perspective: Income/Revenue.
  • Illustrations:
    • Apple Market: Value of apple is $1. Buyer spends $1 (expenditure), seller receives $1 (revenue).
    • Housing Market: House value is $1,000,000. Seller's revenue is $1,000,000; buyer's expenditure is $1,000,000.
    • Other Markets: Fish, smartphone, car markets follow the same principle.
  • Service Market Example: Accounting service
    • The value of service is determined through negotiation.
    • Seller (accountant) provides service, buyer (company) pays.
    • Seller's perspective: Income (salary/wage).
    • Buyer's perspective: Cost/Expenditure.

Gross Domestic Product (GDP)

  • Definition: The total market value of all final goods and services produced in an economy in one year.

Components of the Term "GDP"

  • Gross: Before taxes and depreciation are paid; gross income is revenue minus cost, before accounting for tax and depreciation.
  • Domestic: Production within a country's borders, regardless of the nationality of the producing company or individual.
    • Example: A Japanese company operating in the US contributes to US GDP.
    • A US company operating in China contributes to China's GDP.
  • Product: The goods and services being produced.
  • GDP Calculation: Sum of all products and services produced in a 12-month period (January 1 to December 31).

GDP Illustration

  • Includes all products and services, such as:
    • Farming industry outputs: milk, potatoes, fish, oil, etc.
    • Manufactured goods: iPhones, computers, wine, bicycles, chairs, houses, refrigerators, cars, tractors, airplanes, shoes, etc.
  • All products must be newly produced within the year.
  • Each product has a determined value through buyer-seller agreement.
  • Includes services such as:
    • Installing Zynx, serving food, healthcare, daycare, barber services, teaching, transportation (cabs, airlines), legal services, customer service, social media (Facebook), search engines (Google).
  • Each service has a value people pay for.

GDP, Aggregate Demand, and Aggregate Supply

  • GDP as Total Value: GDP focuses on the product's value at a macro scale.
  • Equivalence: GDP (product value) equals aggregate demand (buyer expenditure) and aggregate supply (seller income).
  • From Micro to Macro: Expands the three aspects of market transactions (product, buyer, seller) to the entire economy.
  • Aggregate Demand/Supply: Knowing one implies the others due to their equivalence.
  • Aggregate Output/Production: Synonymous with aggregate product.

Calculating GDP from the Demand Side

  • Method: Calculate total expenditures in the economy.
  • Four Components (Expenditure Categories):
    • Consumers (C): Personal spending on goods and services (clothes, food, education, healthcare, etc.).
    • Businesses (I): Investment in capital goods (equipment, buildings) to generate income.
    • Government (G): Government spending on goods and services (infrastructure, defense, public services).
    • Foreigners (Exports - Imports): Export (X) - goods and services sold to other countries, tourism. Subtract Imports (M)- good and services bought from other countries.
  • GDP Formula: GDP=C+I+G+(X−M)GDP = C + I + G + (X - M)
    • Where (X−M)(X - M) is net export.

GDP and Business Cycles

  • GDP as a Measurement: GDP is the number that measures economic activity and fluctuates during business cycles.