def update_world(self, change, portfolio_pre, withdrawal):
assert isinstance(change, AnnualChange)
assert isinstance(portfolio_pre, PortfolioSnapshot)
# Because withdrawals happen at the *beginning* of the year, we have to
# calculate the real withdrawal value *before* we apply the current year's inflation
withdrawal_deflated = withdrawal / self.cumulative_inflation
# then we apply that to our portfolio & capture the updated state of the portfolio
self.current_inflation = change.inflation
self.cumulative_inflation *= (1 + change.inflation)
(p_gains, p_val_pre,
p_val_post) = self.portfolio.adjust_returns(change)
portfolio_post = adt.snapshot_portfolio(self.portfolio)
# Now we can finally report this year's activity to our controller
# We need to avoid DivisionByZero in cases where the portfolio is exhausted
if portfolio_pre.value_n == 0:
withdraw_pct_cur = 0
else:
withdraw_pct_cur = withdrawal / portfolio_pre.value_n
return YearlyResults(returns_n=p_gains,
returns_r=((1 + p_gains) /
(1 + self.current_inflation)) - 1,
withdraw_n=withdrawal,
withdraw_r=withdrawal_deflated,
withdraw_pct_cur=withdraw_pct_cur,
withdraw_pct_orig=withdrawal_deflated /
self.portfolio.starting_value,
portfolio_pre=portfolio_pre,
portfolio_post=portfolio_post)
def simulate_accumulation(series,
portfolio=(0, 0),
years=35,
annual_inflow=25000,
accumulation=N_80_RebalanceAccumulation):
portfolio = Portfolio(portfolio[0], portfolio[1])
strategy = accumulation(portfolio).accumulate()
strategy.send(None)
annual = []
for _, change in zip(range(years), series):
gains, _, _ = portfolio.adjust_returns(change)
strategy.send(annual_inflow)
annual.append(
YearlyResults(returns=gains,
withdraw_n=0,
withdraw_r=0,
withdraw_pct_cur=0,
withdraw_pct_orig=0,
portfolio_n=portfolio.value,
portfolio_r=portfolio.real_value,
portfolio_bonds=portfolio.bonds,
portfolio_stocks=portfolio.stocks))
annual_inflow *= 1 + change.inflation
return annual
def simulate_lmp(series, portfolio=(750000,250000), years=40, lmp_real_annual=Decimal('.01')):
count = 0
annual = []
cumulative_inflation = 1
lmp = portfolio[0]
rp = portfolio[1]
for (year, stocks, bonds, inflation) in series:
if count > years:
break
if count < 5:
amount = 50000
else:
amount = 21700
cumulative_inflation *= (1 + inflation)
amount *= cumulative_inflation
previous_portfolio_amount = rp + lmp
rp *= (1 + stocks)
lmp_gains = lmp_real_annual + inflation
lmp *= (1 + lmp_gains)
gains = (rp + lmp) - previous_portfolio_amount
if amount < lmp:
lmp -= amount
else:
a1 = amount - lmp
lmp = 0
if rp > a1:
rp -= a1
else:
amount = rp
rp = 0
annual.append(YearlyResults(
year = 0,
returns = gains,
withdraw_n = amount,
withdraw_r = amount / cumulative_inflation,
withdraw_pct_cur = amount / (rp + lmp),
withdraw_pct_orig = (amount / cumulative_inflation) / (portfolio[0] + portfolio[1]),
portfolio_n = rp + lmp,
portfolio_r = (rp + lmp) / cumulative_inflation,
portfolio_bonds = lmp,
portfolio_stocks = rp
))
count += 1
return annual