Excel offers several easy ways to calculate expiry dates. This post explores different ways to automate expiry date calculations in Excel.

Sales tax is a percentage of a retail price. To calculate it, convert the state sales tax percentage to a decimal, then multiply it by the retail price of the product or service.

It's important to understand how to identify taxable gains and calculate your capital gains tax.

How to Calculate Tax-Equivalent Yield SmartAsset: What is the tax-equivalent yield? To find tax-equivalent yield, all you need is a few pieces of information and a simple formula.

However, at tax time, it can be difficult to calculate your cost basis when you eventually decide to sell the shares you've accumulated over a lifetime of dividend reinvestment.

Consider working with a tax professional: A tax professional can help you plan your withdrawals and income sources to minimize how much of your Social Security is taxed.