Portfolio variance formula excel mmult

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For risk averse investors, it is particularly useful since it can be used as a benchmark before using strategies.

Steps:

➤ Select the output cell (G3) and enter the formula. Alternatively a portfolio variance can be calculated using a CORRELATION matrix, but using the COVARIANCE may be more intuitive.

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Portfolio Variance Formula


Let us take the example of a portfolio that consists of two stocks.

However, the total must be equal to one.

➤ Check that the total weights equal one.

➤ Multiply the transpose of the weights with the variance-covariance matrix to get the weight transpose sigma array. The curly braces in the formula bar indicate an array formula.

➤ To get the variance-covariance matrix divide each element of the transpose matrix with the total number of observations.

Or,

➤ Auto-fill the formula to the rest of the cells.

➤ Set the weights arbitrarily.

Select the 5 cells, enter the formula, and press  Ctrl + Shift + Enter .

➤ The weight transpose sigma matrix is shown below.

➤ To get the portfolio variance, multiply the weight transpose sigma with the weights.

This is just a dummy portfolio variance that needs to be optimized using Excel’s Solver add-in.

➤ Click on the File tab.

➤ Select Options.

Thanks to Excel's covariance matrix and array functionality, we can easily calculate the variance and standard deviation for a portfolio of as many securities as we want.

➤ Drag the Fill Handle tool to copy the formula for the rest of the columns and rows.

➤ Since there are 5 firms, select the cells for the 5 by 5 matrix >> Select all the excess returns >> Press  Ctrl + Shift + Enter .

Note: Remember to press the  Ctrl + Shift + Enter  keys, otherwise you’ll get an error.

To determine which weights in the portfolio produce the minimum variance, you can use Excel’s Solver Add-in to calculate the covariance matrix of returns.

Using 123 daily return observations, we’ll determine the minimum variance portfolio weights for the five assets. To maximize the benefit of diversification more securities are needed, making the textbook method of calculation tedious and prone to error.

Do you have a vague idea of how to measure it but find the implementation daunting? This tutorial covers how to quickly and accurately calculate portfolio volitility for any number of securities.The tutorial is useful for anyone trying to understand diversification of risk, and is a must know for any aspiring Professional Risk Manager(PRM).

Easily Calculate Portfolio Volatility (Standard Deviation) Using Excel

Finance textbooks demonstrate how to calculate variance of a portfolio with two securities, a fairly complex algorithm meant to demonstrate the idea of diversification, however not very realistic.

portfolio variance formula excel mmult

We want to minimize the portfolio variance.
➤ For the By Changing Variable Cells field choose the weights (AB2:AB6).
➤ Click Add to add constraints.

You can add multiple constraints. However, some accounts only have a couple of products. So before doing the matrix multiplication, the variance-covariance matrix must be filtered first.
Below are snips of my power bi and my example calculation in excel using MMULT and Transpose functions (see the formula bar on the snip).

 

It's probably confusing.

All the weights must add up to one
➤ Weight transpose matrix:
➤ Portfolio variance:
➤ Enable Solver: File >> Options >> Excel Add-ins >> Solver Add-in.
➤ Solver: Set objective >> Min >> By Changing Variable Cells >> Constraints >> Solve.

In this article, we’ll learn to make a minimum variance portfolio in Excel using MMULT and TRANSPOSE functions and the Solver Add-in.

Download Practice Workbook


What is a Minimum Variance Portfolio?

A portfolio with the lowest volatility for a particular group of assets is known as the Minimum Variance Portfolio.

This can be accomplished in Excel with MMULT and TRANSPOSE array functions.This tutorial makes use of a COVARIANCE matrix. The risk in SML is beta or systematic risk.

What is the minimum variance curve of a portfolio?

The minimum variance curve or minimum variance frontier represents a set of portfolios with the least variance (risk) for each level of expected return.

How to calculate returns from the adjusted close price?

Returns:


Wrapping Up

In this tutorial, we’ve learned about the minimum variance portfolio and the steps to calculate minimum variance portfolio in Excel using the functions and the Solver add-in.

This method works well if you want to lower portfolio risk without depending on projected returns.

Hi guys,

 

Need your help.

I have a portfolio with various accounts each of which has some products (called risk_curve_month_name in my datasets).

My goal is to be able to calculate portfolio variance based on what accounts were selected (one or a few).

Portfolio variance is calculated through the multiplication of the transposed vector of asset weights by the variance-covariance matrix and multiplied by the vector of asset weights again (this time not transposed).

The weights of assets are already calculated in my power bi: quantity (called exposure in my dataset) * price * variance.

The tricky part is that the variance-covariance matrix consists of all possible combinations of the products.

This blog post explores the minimum variance portfolio and explains how to make a minimum variance portfolio in Excel using simple steps.

➤ A minimum variance portfolio offers the lowest risk for a given expected return.
➤ Excess returns:
➤ Transpose matrix:
➤ Variance-covariance matrix:
➤ Set weights arbitrarily. For example, we’ll add the constraints that the sum of all the weights must equal one and the weight for NVDA should be at least zero.
Other constraints include all the weights must be greater than zero or that some weights should be negative (shorting stocks).
➤ The sum of the weights equals one: Select AB7 cell >> Choose equal to >> enter 1 >> Add.

➤ The weight for NVDA should be at least zero: Select AB5 cell >> Choose greater than equal to >> Enter 0 >> OK.

➤ Check all the inputs and hit the Solve button.

➤ Check Keep Solver Solution >> OK.

Based on the Solver results our portfolio should have the following weights for each stock:

➤ Toyota Motor Corporation: 10%
➤ Walmart Inc.: 35%
➤ Chevron Corporation: 29%
➤ Nvidia Corporation: 2%
➤ Microsoft Corporation: 23%

➤ For each of the five assets, you will obtain a different weight.

➤ You’ll get the transpose matrix. So please ask me a question if anything is unclear.

 

Many thanks for your time and help. The total weight adds up to 1.
➤ Based on past data, these weights will return the lowest portfolio standard deviation.
➤ Note how diversification among assets with weak or negative correlations helps to lower total volatility.
➤ The minimum variance portfolio configuration can be used as a standard against which other portfolios (such as equal weighted or max Sharpe) can be compared.


FAQ

What is portfolio variance?

Portfolio variance measures the risk of a portfolio based on the variance of each asset in that portfolio.

How to minimize portfolio variance?

Portfolio variance can be minimized by selecting stocks with negative or low correlation.

What is the difference between CML and SML?

CML shows the rate of return for a certain portfolio.