I just had this problem myself. A simple solution, not 'the solution' (as i believe you can pay for this function to be added to excel), is as follows: (NB. This can be checked with reference to the GEOMEAN function).
e.g. your data is in column A (A3-A33)
in cell B3 type =LN(A3) (i.e. the natural log)
copy and paste down to B33.
In B34, calculate the standard deviation of the loged numbers i.e. =STDEV(B3:B33)
In A34 type =EXP(B34) This is your geometric standard deviation!!
You can check this method with ref. to the GEOMEAN function.
Take the mean of column B. i.e. in cell B35 type =average(B3:B33)
In cell A34 type =EXP(B34).
This should returen the same answer as =GEOMEAN(A3:A33)
There is an error in the above mentioned function which is:
//In B34, calculate the standard deviation of the loged numbers i.e. =STDEV(B3:B33)
Here do not calculate the STDEV(b3:b33) instead, calculate the =AVG(b3:b33)
Use the STDEV() function.
=stdev(...) will return the N-1 weighted sample standard deviation. =stdevp(...) will return the N weighted population standard deviation.
Here's how you do it in Excel: use the function =STDEV(<range with data>). That function calculates standard deviation for a sample.
A worked out example is shown in the related link. There are a number of calculators that do this automatically. Also, the Excel program (and most other spreadsheet programs) include a standard deviation function. In Excel, it is +stdev(a1:a10) for a list of numbers from a1 to a10.
See the related links on how to calculate standard deviation. If there are more than a dozen data points, it is tedious to calculate by hand. Use excel or an online calculator. To get 2 standard deviations, multiply the calculated std deviation by 2.
Putting the data into excel, the std dev for the sample is 6.20
The order in which Excel will perform calculations.
yes you can do math in excel, it is very easy.
The main reason for Excel is to perform calculations.
Used the GEOMEAN function on Excel and the answer it gave was 20.
See excel help file it's very easy
The Sharpe Ratio is a financial benchmark used to judge how effectively an investment uses risk to get return. It's equal to (investment return - risk free return)/(standard deviation of investment returns). Standard deviation is used as a proxy for risk (but this inherently assumes that returns are normally distributed, which is not always the case). See the related link for an Excel spreadsheet that helps you calculate the Sharpe Ratio, and other limitations.