I'm not sure if there is a limit to the amount of figures basically choose nvarchar(MAX), and I am unsure the number of figures I'd need anyways.

What is the standard data type to make use of here? I am using SQL Server 2008 R2

The ntext type is deprecated, much like text and image. Microsoft suggests changing all of them with nvarchar(max), varchar(max) and varbinary(max) correspondingly.

Use nvarchar(max), therefore.

Reference:

The benefits of using nvarchar(MAX) are that you could run functions for example Replace, Left, Len etc on nvarchar(MAX) but this is not on ntext. ntext local variables also can't be produced in saved methods however nvarchar(MAX) can.

ntext can also be apt to be deprecated later on towards nvarchar(MAX) see:

ntext, text, and image

The default setting for NVARCHAR(MAX) would be to store its text value within the table structure, unless of course the written text has ended 8,000 bytes (that is 4000 double-byte chars), after which it reacts as an NTEXT and stores the written text value within the LOB, and stores a pointer towards the text within the table - which provides much worse performance.

In a nutshell, choose NVARCHAR(4000), as lengthy as it is OK to get rid of bytes over 8K lengthy.

If you do not know the number of you'll need I'd use varchar(MAX). I believe the limit is 8000 for varchar(MAX) and 4000 for nvarchar(MAX)

Be cautious though, do not must many posts inside your database such as this. If you're able to create a reasonalbe estimation get it done.