Can anyone tell me how to create a formula for downside deviation in excel? Downside deviation considers only returns that fall below a defined Minimum Acceptable Return (MAR) rather then the arithmetic mean. For example, if the MAR is assumed to be 10%, the downside deviation would measure the variation of each period that falls below 10%. For the following stream of returns (50 observations), the downside deviation (assuming an MAR of 10%) is approximately 0.95% (or 3.29% annualized). Further info on the definition can be found at

http://support.pertrac2000.com/statistics2000.asp. I just am having trouble building a formula in excel...any help would be greatly appreciated. Thanks in advance

7.10

4.20

4.00

4.90

4.80

5.30

(2.10%

2.80

0.60

2.10

3.00

2.90

1.50

4.10

3.20

(1.50%

2.00

2.20

(1.70%

2.90

0.20

0.20

3.10

(0.60%

2.60

1.10

2.20

4.30

5.40

(0.10%

2.00

1.40

(0.90%

2.20

0.50

1.90

(1.50%

3.00

2.30

0.90

(2.10%

0.20

5.90

1.90

2.10

(0.90%

3.20

3.40

0.60

(0.50%