Notes on Price Level Concepts: Unemployment, CPI Biases, Inflation, and Time Adjustment

Unemployment: frictional, structural, and cyclical

• Definitions refresh (unemployment types):
  • Frictional unemployment: short-term unemployment when people are between jobs or searching for a better match; not due to lack of skills. Usually reflects voluntary movement and job matching frictions.
  • Structural unemployment: unemployment due to a mismatch between workers’ skills and job requirements, or because the underlying industries have changed (skills obsolete or obsolete jobs). Requires retraining or investing in new skills.
  • Cyclical unemployment: unemployment caused by the business cycle ( demand shortfalls ); occurs when there are not enough jobs overall.
• Transcript example distinctions:
  • Case: You’re fired, but nothing in the case says you can’t do the job. This suggests frictional unemployment (you’re capable, but still searching for a match).
  • If the scenario said you’re terrible at the job, it would indicate a lack of capability and is not frictional.
  • An employer finding another match and you having the skills but still being unemployed is frictional because the frictions in matching exist.
  • John being fired as a telemarketer is described as structural because the job’s nature or market for that role changes, not due to your skill in general.
• How to distinguish in general:
  • If the job that exists is removed or there’s no job available, that’s cyclical.
  • If there is a job but the person lacks the required skills, that’s structural.
  • If there is a job and the person has the skills but is in transition or seeking a better match, that’s frictional.
• Metaphor: Matching workers to jobs is like dating; friction exists in the process of finding a good fit, not just a lack of ability.

Big Horizons: three-step rate problem and calculations

• Given data:
  • Frictional unemployment rate (u_f) = 2%
  • Overall unemployment rate (u) = 7%
  • Civilian working-age population = 100,000,000
  • Employed = 82,000,000
• Step 1: Solve for labor force and unemployment using the unemployment rate definition
  • Let LF be the labor force; U be the number unemployed; E be employed.
  • u = U / LF, so U = u · LF.
  • Also, LF = E + U.
  • Substitute: LF = E + u · LF → LF(1 − u) = E → LF = E / (1 − u).
  • Compute: LF = 82,000,000 / (1 − 0.07) = 82,000,000 / 0.93 ≈ 88,172,043.
  • Unemployed: U = u · LF ≈ 0.07 × 88,172,043 ≈ 6,172,043.
• Step 2: Labor force participation rate (LFPR)
  • LFPR = LF / Working-age population = 88,172,043 / 100,000,000 ≈ 0.8817 ≈ 88.17%
• Step 3: Cyclical and structural unemployment rates (using natural rate NR and frictional rate f)
  • Given natural rate NR = 5%, frictional rate f = 2% (as a share of LF).
  • Cyclical unemployment rate = actual rate − NR = 7% − 5% = 2%
  • Structural unemployment rate = NR − f = 5% − 2% = 3%
• Quick summary of results (rates as % of LF):
  • LFPR ≈ 88.17%
  • Unemployment rate u = 7%
  • Cyclical unemployment rate ≈ 2%
  • Structural unemployment rate ≈ 3%
• Quick counts (optional):
  • Unemployed count U ≈ 6.17 million
  • Labor force LF ≈ 88.17 million

Price level indexes and how inflation is measured

• CPI and biases overview
  • Substitution bias: CPI assumes fixed basket; consumers substitute cheaper goods when relative prices change, leading to an overstatement of inflation.
  • Outlet bias: shoppers switch among stores (e.g., full-service stores to discount outlets); CPI estimates may lag as consumer substitutions are not fully captured.
  • Quality bias: some price increases reflect genuine quality improvements; harder to adjust for quality, can overstate or understate true inflation.
  • Hedonics: a method to quantify quality changes in dollar terms; e.g., pricing an upgrade in tech gear by estimating the value of added features.
  • New product bias: new products replacing old ones may be cheaper or more expensive; CPI can mis-measure inflation if the basket doesn’t adapt quickly.
• How CPI and other indexes are constructed
  • All price level indexes use the formula: Index = \frac{Expenditures\ on\ market\ basket\ in\ current\ period}{Expenditures\ on\ market\ basket\ in\ base\ period} \times 100
  • Basket definition differences:
  • CPI uses a basket based on typical American household purchases (survey-based).
  • PPI (Producer Price Index) measures prices paid by firms, including final and intermediate goods; tends to be more focused on inputs and can serve as a leading indicator for CPI.
  • ECI (Employee Cost Index) measures changes in costs of living for employees; can influence wage dynamics and price setting.
  • GDP deflator measures prices of all domestically produced goods and services included in GDP (C + I + G + NX) and includes both final and some intermediate goods via GDP composition; broader than CPI.
• The Fed’s inflation barometer
  • The Fed’s primary policy barometer is often associated with PCE (Personal Consumption Expenditures) price index, which is similar to CPI but uses a different weighting and substitution method.
  • The GDP deflator is broader than CPI and tracks inflation across all components of GDP, including government spending and net exports.
  • The different indexes move together over time but can diverge in short-run movements due to basket composition and methodological differences.

Inflation concepts and historical context

• Inflation, deflation, disinflation, and related concepts
  • Inflation: a rise in the overall price level over time.
  • Deflation: a sustained fall in the overall price level.
  • Disinflation: a slowdown in the rate of inflation (prices still rise, but more slowly than before).
  • Stagflation: simultaneous stagnation (slow GDP growth) and inflation; historically prominent in the 1970s in many economies.
  • Hyperinflation: extremely high and typically accelerating inflation; e.g., in countries like Zimbabwe and, historically, Germany (1920s).
• Historical examples and intuition
  • Hungary (1946) and Zimbabwe (late 2000s) experienced extreme hyperinflation driven by excessive money printing and loss of confidence in the currency.
  • Germany after WWI experienced hyperinflation around 1923 due to reparations and monetary expansion, leading to price levels doubling extremely rapidly.
  • World wars and large social welfare programs (e.g., LBJ’s Great Society) contributed to inflationary pressures via large fiscal outlays.
• Understanding long-run price level trends
  • Inflation tends to persist and evolve over decades, with periods of high inflation (e.g., 1960s–1980s), disinflation (late 1980s–1990s), and recent episodes depending on policy and demand-supply dynamics.
• Relationship between monetary policy and inflation
  • The Fed uses the money supply and related monetary policy to influence inflation; higher money supply generally supports higher price levels in the short run, while restrictive policy can reduce inflation over time.

Calculating inflation and time adjustment with price indexes

• Basic inflation calculation between consecutive years
  • If Indext is the price index in year t and Index{t-1} is the index in year t−1, then:
  • \pi{t-1\rightarrow t} = \left(\frac{Indext}{Index_{t-1}} - 1\right) \times 100\%.
• Inflation relative to a base year
  • If the base year index is 100, then inflation from the base year to year t is:
  • \pi{\text{base}\rightarrow t} = \left(\frac{Indext}{Index{\text{base}}} - 1\right) \times 100\% = (Indext/100 - 1) \times 100\%.
• Later-year dollars vs earlier-year dollars (purchasing power)
  • The value of money changes with the index; to convert an amount from an earlier year to a later year:
  • \text{LaterYearDollars} = \text{EarlierYearDollars} \times \frac{Index{\text{later}}}{Index{\text{base}}}.
  • Example framework from the transcript: an amount in the earlier year can be converted to its later-year purchasing power by multiplying by the ratio of the later-year index to the base-year index.
• Example worked concepts (from transcript demonstrations)
  • If a hypothetical CPI base year has 100, and it rises to 110 in the next year, the inflation rate is \left(\frac{110}{100}-1\right)\times100 = 10\%.
  • If it then rises to 125 by a later year, the inflation from base year is \left(\frac{125}{100}-1\right)\times100 = 25\%.
  • If you compare non-base-year values, do not simply subtract; use the ratio formula to avoid misestimation (e.g., from 110 to 125 gives roughly 13.64% inflation: \left(\frac{125}{110}-1\right)\times100\% \approx 13.64\%.)
• Practical example: Babe Ruth earnings and the changing price level
  • Concept: convert historical earnings to present dollars to understand purchasing power using a price index multiplier.
  • Example setup (as in the transcript): 1932 salary = $80,000. Using the CPI multiplier to a present year gives an approximate present purchasing power around $2,000,000 per year for that level of earnings, illustrating how much price levels have changed.
  • Formula used conceptually: ext{PresentValue} = ext{PastValue} \times \frac{Index{\text{present}}}{Index{\text{past}}}.
• Example of a simple relative value across a very long horizon
  • If $1 today equals about a few cents in 1914 purchasing power (roughly 4¢ in the transcript’s framing), that illustrates how much purchasing power has eroded over a long run due to inflation.
  • General takeaway: over long horizons, even small annual inflation compounds to large changes in purchasing power.
• Practical retirement planning thought experiment
  • If today’s income is $75,000 and the price level triples by 2065, to maintain the same real purchasing power you’d need approximately $225,000 in 2065 dollars (i.e., $75,000 × 3 = $225,000).
  • Simple rule of thumb: if the price level grows by a factor F, to preserve your current standard of living you’d aim for an income multiplied by F.
• Summary takeaways for exam-oriented study
  • Know how to classify unemployment types and apply the NR/FR framework.
  • Be able to compute LF, LFPR, U, and rates of cyclical/structural unemployment from a given data set.
  • Understand the major price level indexes (CPI, PPI, ECI, GDP deflator, PCE) and what each measures.
  • Recognize biases in CPI calculations and how hedonics and new-product bias affect reported inflation.
  • Be able to perform simple inflation calculations across years and understand base-year vs non-base-year comparisons.
  • Understand the concept and potential real-world implications of inflation paths, disinflation, stagflation, and hyperinflation, with notable historical examples.
  • Apply the time-value concept to convert past dollars to present dollars using price indexes and explain the practical implications for earnings, retirement planning, and cost of living over long horizons.