zfin/examples/post-retirement-smile/projections.srf

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#!srfv1
# Post-retirement projection with a declining ("spending smile") model.
#
# Same retired couple as the post-retirement/ example - Robin (born
# 1958) and Jamie (born 1961) - but this variant demonstrates the
# spending_change feature: real spending is not held flat, it drifts.
#
# The Blanchett "spending smile": retirees spend more in the early
# "go-go" years, taper through the "slow-go" years, then spending
# rises again late as healthcare costs dominate the "no-go" years.
# zfin models the two limbs separately:
#
# 1. The declining limb is `spending_change` below (-2%/yr real).
# 2. The late-life rise is the Healthcare life event (age 80),
# already an expense record - no special-casing needed.
#
# Composing those two produces the U-shaped smile, and the
# "Lowest spending: ... in year N" callout under the Safe Withdrawal
# table reports the bottom of the U in today's dollars.
# Allocation target shifts more conservative in retirement
type::config,target_stock_pct:num:60
# Real spending declines 2%/yr through retirement (negative = decline,
# positive would model a rising real spend). Whole percent; absent =
# flat real spending, the default.
type::config,spending_change:num:-2
# Distribution horizons - through age 90 (older partner first)
type::config,horizon:num:20
type::config,horizon:num:30
type::config,horizon_age:num:95
# Birthdates
type::birthdate,date::1958-02-19
type::birthdate,date::1961-07-04,person:num:2
# Social Security - both already collecting. Income reduces the
# portfolio withdrawal but is NOT counted as spending, so it does not
# move the spending-trough callout.
type::event,name::Social Security (Robin),start_age:num:67,person:num:1,amount:num:34800
type::event,name::Social Security (Jamie),start_age:num:65,person:num:2,amount:num:28200
# Late-life healthcare bump - the rising limb of the smile. Modeled as
# a recurring expense starting at age 80 for the older partner (a
# realistic long-term-care figure). It is large enough to outweigh the
# base decline once it starts, so the spending trough lands in
# mid-retirement - the year just before age 80 - rather than the final
# year. That mid-trajectory minimum is exactly what the trough callout
# is for.
type::event,name::Healthcare (late-life),start_age:num:80,person:num:1,amount:num:-55000