theorem tax_wedge_on_MPK {τ₁ τ₂ ρ_time δ : ℝ}
(_hτ₁ : τ₁ < 1) (_hτ₂ : τ₂ < 1) :
eulerSteadyStateMPK τ₂ ρ_time δ - eulerSteadyStateMPK τ₁ ρ_time δ =
eulerSteadyStateReturn τ₂ ρ_time - eulerSteadyStateReturn τ₁ ρ_time := by
simp only [eulerSteadyStateMPK, eulerSteadyStateReturn]; ringAccumulation Dynamics (Layer 2 of Macro Extension)