Conditional Column not working (M against Measure)

Hi,

If I use 

Type of Sale = IF(insertBK[ClassOfBusiness] = "Bus Acc","BA",IF(insertBK[TrueCompany]="HOUSE ADVERT","House",IF(insertBK[iadclass] = 9014, "Local Remnant"," ")))

In a measure it works fine.

However if I try and to use it in a calculated column ie

 #"Added Conditional Column" = Table.AddColumn(#"Removed Blank Rows", "Type of Sale", each if [ClassOfBusiness] = """BUS ACC""" then "BA" else if [TrueCompany] = """HOUSE ADVERT""" then "House" else if [iadclass] = 9014 then "Local Remnant" else if [SourceCode] = """BA430""" then "National" else if [SourceCode] = """CA148""" then "National" else if [SourceCode] = """HX355""" then "National" else if [SourceCode] = """MD301""" then "National" else "local" )

It doesnt work and only classifies 'Local Remant'.

Any ideas?

Thanks

Chris