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Performance Of The German Pension System

Section 1 - Comprehensive Analysis: German Pension System Contributions, Subsidies, and Returns

Table 1: Federal Pension Subsidies as Share of Federal Revenue

Source: Bundeshaushalt.de, Rentenversicherungsberichte (DRV), EU Ageing Report 2024

Decade Avg Pension Subsidy (€ bn/year) Avg Federal Revenue (€ bn/year) % of Revenue Spent on Pensions
1950s ~1 ~20 ~5%
1960s ~2.5 ~40 ~6%
1970s ~5 ~70 ~7%
1980s ~10 ~120 ~8%
1990s ~20 ~250 ~8%
2000s ~40 ~400 ~10%
2010s ~80 ~600 ~13%
2020s ~100 ~700 ~14%

This table reflects the growing role of tax-funded transfers into the pension system.

Table 2: Effective Pension Contributions as % of Gross Income

Includes employee, employer, and tax-funded equivalent share
Sources: DRV Finanzberichte, BMAS Rentenberichte, EU Ageing Report 2024, Destatis National Accounts

Decade Employee Rate (%) Employer Rate (%) Estimated Tax-Funded Equivalent (%) Total Effective Burden (%)
1950s ~7.0 ~7.0 ~1.0 ~15%
1960s ~7.5 ~7.5 ~1.5 ~16.5%
1970s ~8.5 ~8.5 ~2.0 ~19%
1980s ~9.5 ~9.5 ~3.0 ~22%
1990s ~9.75 ~9.75 ~3.5 ~23%
2000s ~9.75 ~9.75 ~5.0 ~24.5%
2010s ~9.3 ~9.3 ~6.5 ~25.1%
2020s ~9.3 ~9.3 ~7.3 ~25.9%

Assumptions: - Tax-funded share derived by dividing federal subsidies by total labor income (approx. €1.5 trillion in the 2020s). - Assumes the entire federal subsidy is effectively borne by taxpayers as a uniform income burden.

Table 3: Income Paid In vs. Pension Paid Out (Replacement Rate)

Sources: DRV, BMAS, OECD Pensions at a Glance, EU Ageing Report 2024

Decade Effective Total Contribution (% of gross income) Average Replacement Rate (% of final gross income)
1950s ~15% ~70%
1960s ~16.5% ~65%
1970s ~19% ~60%
1980s ~22% ~55%
1990s ~23% ~52%
2000s ~24.5% ~50%
2010s ~25.1% ~48%
2020s ~25.9% ~47%

Section 2 - Counterfactual Analysis: What If We Invested Pension Contributions into an ACWI ETF?

Scenario

What if, instead of Germany’s statutory pay-as-you-go (PAYG) model, the entire 25.9% of gross income paid into the system were invested in a global equity fund such as the MSCI ACWI ETF?

Assumptions

  • Contribution rate: 25.9% of gross income (for 2020s)
  • Working life: 45 years (ages 22–67)
  • Retirement duration: 20 years (ages 67–87)
  • Real ACWI return: ~5% annually (after inflation, fees)
  • Constant annual contributions: 25.9% of €42,000 = €10,878/year
  • Contributions indexed with 2% wage growth, compounding annually

Mathematical Model

Step 1: Accumulated Wealth at Retirement

Using future value of growing annuity: Where: - Initial contribution (C) = €10,878 - Return rate (r) = 5% = 0.05 - Wage growth rate (g) = 2% = 0.02 - Years of contribution (n) = 45 $$FV = C \cdot \frac{(1 + r)^n - (1 + g)^n}{r - g}$$

Step 2: Sustainable Withdrawal Over Retirement

Use annuity formula to withdraw over retirement period: Where: - Present Value (PV) = FV from Step 1 - Return rate (r) = 0.05 - Retirement years (n) = 20 $$PMT = PV \cdot \frac{r(1 + r)^n}{(1 + r)^n - 1}$$

Step 3: Replacement Rate Calculation

Where: - Initial salary (S₀) = €42,000 - Wage growth rate (g) = 2% = 0.02 - Working years (n) = 45 - Final salary (S) = S₀ × (1 + g)^n - Annual pension (P) = PMT

$$\text{Replacement Rate} = \frac{P}{S} \times 100\%$$

Implementation

def calculate_replacement_rate(contribution_rate, years=45, return_rate=0.05, wage_growth=0.02):
    # Convert percentage to decimal
    contribution_rate = contribution_rate / 100

    # Calculate future value
    initial_contribution = 42000 * contribution_rate
    fv = initial_contribution * ((1 + return_rate)**years - (1 + wage_growth)**years) / (return_rate - wage_growth)

    # Calculate withdrawal
    withdrawal = fv * (return_rate * (1 + return_rate)**20) / ((1 + return_rate)**20 - 1)

    # Calculate replacement rate
    final_salary = 42000 * (1 + wage_growth)**years
    replacement_rate = (withdrawal / final_salary) * 100

    return replacement_rate

# Test all decades
decades = {
    '1950s': 15,
    '1960s': 16.5,
    '1970s': 19,
    '1980s': 22,
    '1990s': 23,
    '2000s': 24.5,
    '2010s': 25.1,
    '2020s': 25.9
}

for decade, rate in decades.items():
    fair_rate = calculate_replacement_rate(rate)
    print(f"{decade}: {fair_rate:.1f}%")

1950s: 107.8% 1960s: 118.5% 1970s: 136.5% 1980s: 158.0% 1990s: 165.2% 2000s: 176.0% 2010s: 180.3% 2020s: 186.0%

Table 4: Comparison of Current System vs Fair System (ETF Investment)

Decade Effective Total Contribution (% of gross income) Current System Replacement Rate (% of final gross income) Fair System Replacement Rate (% of final gross income)
1950s 15% 70% 107.8%
1960s 16.5% 65% 118.5%
1970s 19% 60% 136.5%
1980s 22% 55% 158.0%
1990s 23% 52% 165.2%
2000s 24.5% 50% 176.0%
2010s 25.1% 48% 180.3%
2020s 25.9% 47% 186.0%

Note: Fair System assumes the same contribution rate is invested in a global equity ETF with 5% real annual return, 2% wage growth, 45-year accumulation period, and 20-year retirement period.

Interpretation

  • If the same money were invested privately into global equities with 5% real return, the result would be roughly 4× the payout: 186% vs current 47%.
  • This exposes the opportunity cost of PAYG under low population growth.