Calculating how far a number has declined from one year to the next is pretty easy if you are only considering a one year period. You subtract the current year's number from last year's number, then ...

Investopedia contributors come from a range of backgrounds, and over 25 years there have been thousands of expert writers and editors who have contributed. Robert Kelly is managing director of XTS ...

Calculate average percentage difference by subtracting, then dividing price differences. Average percentage difference helps foresee market trends and irrational periods. Understanding this metric can ...

An amount can be increased or decreased by a certain percentage to change its size. A reverse percentage problem involves finding the original amount before a percentage increase or decrease. The ...

There are many situations in investing in which it makes sense to look at how two different numbers related to each other over time. Whether you're talking about two stocks in the same industry, the ...