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Blog - page 8
More guides and examples for calculators, formulas and useful everyday concepts.
Articles
Page 8 of 10.
Finance · 5 min read
Successive discounts: why 20% + 10% is not 30%
Calculate stacked discounts in sequence and convert them into one equivalent effective discount.
Read articleMath · 5 min read
Reverse percentages: how to find the original value
Recover an original value from a final amount after a discount, increase, tax or markup.
Read articleMath · 6 min read
Percentage formulas in Excel and Google Sheets
Use spreadsheet formulas for percentages, discounts, increases and changes without double-counting percent formatting.
Read articleMath · 5 min read
Percentage difference vs. percentage change
Choose the correct formula depending on whether values have a meaningful starting point or are peers being compared.
Read articleMath · 5 min read
How to convert fractions and decimals to percentages
Move between fractions, decimals and percentages with simple operations and familiar equivalences.
Read articleFinance · 7 min read
Compound interest for retirement: 20-, 30- and 40-year examples
See how time and monthly contributions affect a hypothetical retirement balance over 20, 30 and 40 years.
Read articleFinance · 7 min read
CETES and compound interest: what happens when you reinvest?
Understand how reinvesting Mexican Treasury bills can create compounding, which inputs matter and why a fixed-rate model has limits.
Read articleFinance · 6 min read
Inflation and compound interest: calculate real value
Learn how inflation erodes purchasing power and convert the future value of an investment into today’s money.
Read articleFinance · 6 min read
How much should you save each month to reach a goal?
Calculate the monthly contribution needed for a savings goal using your target, time horizon and assumed return.
Read articleFinance · 7 min read
Common compound interest calculator mistakes
Avoid errors involving rates, terms, inflation, contributions, taxes, compounding frequency and rounding.
Read articleMath · 5 min read
Percent vs. percentage points: what is the difference?
Interpret changes in rates, polls and taxes correctly by separating relative percent change from percentage-point change.
Read articleMath · 4 min read
Percentage decrease: formula and examples
Calculate how much a value fell relative to its original amount and avoid using the wrong baseline.
Read article