Estimates for rates of return during retirement should generally be more conservative than estimates for rates of return during the accumulation phase. Investors are more willing to take risk while they are still working than they are after they are retired. For example, while working an investor may try to achieve a 7.5% return on his/her investments whereas s/he may be willing to be satisfied with a less risky 4.75% return during retirement.Entries of 15 or less will be treated as a percentage. Entries greater than 15 will be treated as a dollar amount.Inflation erodes your purchasing power. Not all items are affected equally. A fixed-rate mortgage can be used to offset some inflation since it is repaid in "deflated" dollars. Try changing the input to see what effect this has on your investment account and savings requirements. This is the amount of "spendable" income you want during your first year of retirement. This amount will increase by the rate of inflation that you enter below.Your average tax bracket is estimated by dividing the tax you pay by your total income from all sources, whether this income is required to be reported on your tax return or not. The deductions you take on your tax return are not considered in arriving at this number. Your average tax bracket during retirement may be different than your average tax bracket while working.