Replacement Rate
Also called: income replacement ratio, pension replacement rate
The replacement rate is the share of pre-retirement income your retirement income covers, with 70–80% the usual planning target. The logic behind a number below 100% is that retirement removes payroll taxes, commuting, and retirement saving itself. It's a rule of thumb rather than a finding: someone who paid off a mortgage needs far less, and someone facing long-term care costs may need more.