Simple demo attached, illustrating the use of DATEDIFF formula in the scenario where investments/deposits have different maturity date.
First step is calculation of number of days between today and the investment maturity date:
DATEDIFF(NOW, [Date], "days")  

By using NOW function, this calculation will keep the report up-to-date, always returning the latest breakdown.
It is also possible to 'fix' the date and use DATEVALUE("dd/MM/yyyy") instead of NOW, e.g. DATEDIFF(DATEVALUE("01/10/2015"), [Date], "days") .
Second step is to create irregular time intervals, that will 'bucket' the records and be used for sum calculation.

IF(
[Difference days]<1,"matured",
[Difference days]<2,"1 day",
[Difference days]<8,"1 week",
[Difference days]=<31,"1 month",
[Difference days]<92,"3 months",
[Difference days]<184,"6 months",
[Difference days]<366,"1 year",
[Difference days]<1096,"3 years",
[Difference days]<1827,"5 years",
[Difference days]<2557,"7 years",
[Difference days]=<3653,"10 years",
[Difference days]>3653,"over 10 years",
null)  

Aggregation and summing of investment amounts for each period is done in the Bar/Line view.