how to use a standard deviation function in qlik sense

[coloful_architect]

hi guys,

Trying to use stdev to address a business question. I have fields: customers, suppliers, sales. 

Each customer could have several suppliers. Trying to find out which customer has suppliers with a more dispersed pattern like supplier A 25%, supplier B 25%, supplier C 25% and supplier D 25%

Not like supplier A 98%， supplier B 2%.

I believe a relatively small number of stdev would shred some lights.

but I am now wrapping my head around using the function at a table.

how I can use stdev and apply with a set expression to filter out sales less than 0 ?

I want to insert into a table with this format 

customer

supplier

units

Std value

or pivot table

customer supplier A, supplier B, supplier C,..... units, Std value 

[coloful_architect]

I tried this but end up with blank cells....

StDev(aggr(sum([Pack Units]), distinct Manufacturer))

[Coloful_Black · Accepted solution]

slight tweak by adding supplier

=stdev(
aggr(sum([Pack Units]), [Business Name],Supplier))