What function is used to aggregate the row (column)

[#1]

Excuse me !

What function is used to aggregate the row (column), for example

Returns the first [Date] of the [sales rate] of 0.8     ( note: Date is Variable)

Such as   A001  :   Return  [2016-1-5]

               A002  :   Return  [2016-1-4]

Returns the first [Date] of the [Inventory Turn] of 0.1  ( note: Date also is Variable)

Such as   A001  :   Return  [2016-1-1]

               A002  :   Return  [2016-1-2]

How to find out these “first [Date]”？？？？？

[#2]

Hi Sunny T,

    First ,Thank you very much for your kind help !

    I used your Expressions to calculate ,but  result is wrong.

    Would you help me again!

    The following questions

[sunny_talwar]

How is this accumulation related to your initial discussion of getting the dates in the table below? Would you be able to elaborate as to what were you expecting to see in that table?