Annual Growth Formula

Here is another Javascript calculator I created to allow me to quickly determine the annual growth rates of my investments. This is done based on the following entries: original cost (c), current value (v), and the number of months that have passed since the original investment (m). The formula used can be seen in the image that accompanies this paragraph.

You don't know how many months you've had something and only know the number of years? Well, of course just multiply the years by 12 to get the months. If you want, you can use this quick calculator which will put the result in the main calculator for you:

# of years:

equals this many months:

Many of my investments I have added to periodically throughout the years so this calculator can't be used to determine the exact annual return. (That would take multiple calculations and one complex formula to account for all possible investments and time frames). Instead I just enter the total I've invested throughout the life of the investment as the original cost and know that the annual return given is understated. The result still serves as a basis from which I can compare one investment to another.

The annual return (a) is displayed as a percentage and not a proportion (the calculator divides the result of the calculation by 100 for you).

Original cost(c) - $:	Current value(v) - $:
# months held(m):	Annual return(a) - %:

Yes, this will also show you an annualized loss if you have one (a negative percentage)!