I am trying to calculate Month over Month % change on data rows. For example my current output is:

```
DataDate |LocationId|Payment|MoM [Current placeholder column in script]             
12-1-2013|LocationA |$5.00  |      
1-1-2014 |LocationA |$10.00 |    
2-1-2014 |LocationA |$100.00|   
12-1-2013|LocationB |$50.00 |    
1-1-2014 |LocationB |$25.00 |    
2-1-2014 |LocationB |$50.00 |

```

I am pasting the results into Excel and then calculating the MoM by using the following formula:  

 ((CurrentDataDate Payment/PreviousDataDate Payment)-1)] 

I can not figure out where to even begin trying to accomplish this so I cant provide any coding from what i have tried...I have read about and attempted a correlated scalar query used to calculate running totals and tried to alter it to accomplish this...no dice...I tried with a Join and a subquery but i will admit my subquery abilities are less than adequate.

The code used to call this info is:

```
Declare @BeginDate as DateTime
Declare @EndDate as DateTime    
Set @BeginDate = '12-01-2013'
Set @EndDate = '02-01-2014'

Select DataDate,LocationId,Payment,0 as MoM
From dbo.mytableview
Where DataMonth between @BeginDate and @EndDate

```

Desired output is:

```
DataDate |LocationId|Payment|MoM              
12-1-2013|LocationA |$5.00  |      
1-1-2014 |LocationA |$10.00 |1.0  [or 100%]  
2-1-2014 |LocationA |$100.00|9.0  [or 900%] 
12-1-2013|LocationB |$50.00 |    
1-1-2014 |LocationB |$25.00 |-.50 [or -50%]  
2-1-2014 |LocationB |$50.00 |1.0  [or 100%]

```

I am using Microsoft SQLServer 2008 R2. I also have/and can use the 2012 version if that is needed.