AVERAGEX over time intervals

[Termigez]

Hello everyone, I want to create a new calculated column that will iterate through my rows and will return an average value for current and past 2 values for each unique name taking into consideration Time 

Name	Time	Amount	EXPECTED RETURNED VALUE
A	10:00	4	(can be null or 4)
B	10:00	5	(can be null or 5)
A	11:00	3	(can be null or 3.5)
B	11:00	1	(can be null or 6)
A	12:00	1	8 (4+3+1) / 3 = 8/3
B	12:00	5	11(5+1+5) / 3 = 11/3
A	13:00	6	10 (3+1+6) / 3 = 10/3
B	13:00	3	9 (1+5+3) / 3 = 3
A	14:00	5	12 (1+6+5) / 3 = 4

Why I need this? Because I want to create a line chart that will use Time as X axis and for each hour it will show an average value for this hour and two past hours. As you can see above the function for Name = A and Time = 14:00 returns average base on Amount from 12:00, 13:00 and 14:00 where Name = A. It is also important to note that there is more than one date in my data so please have in mind that Name = A, Time = 10:00 can occure multiple times but with different date. So I suppose the challange is to create and index that will take into consideration both Date, Time and Name and then use this Index to interate over Amount? 

[Anonymous · Accepted solution]

@Termigez 

You first need to create an Index for the [Time], so you can look back for a range, because Time type is not supported 

Index = RANKX('Table',[Time],,ASC,Dense)

Result = CALCULATE(AVERAGE('Table'[Amount]),FILTER('Table',[Name]=EARLIER('Table'[Name])),FILTER('Table','Table'[Index]<=EARLIER('Table'[Index])&&'Table'[Index]>EARLIER('Table'[Index])-3))

Paul Zheng
If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

[amitchandak]

@Termigez 

Try one of the two as columns

Avg  = avergageX(filter(table,table[Name] =earlier(table[Name]) && table[time] <=earlier(table[time])),table[Amount])

Avg  = avergageX(filter(table,table[Name] =earlier(table[Name]) && table[time] <earlier(table[time])),table[Amount])

[Termigez]

Unfortunately those formulas don't work. I would appreciate any other ideas.