Dataport will export an extra blank line

The main purpose of this requirement is to export vendor and it's bank account data into file then import into another company after user has revised the file.

I've define 2 dataitems in this dataport (Import = No)
(1)Integer: CONST(1)
(2)Vendor: Vendor Type=FILTER(EMPLOYEE)

(1) to export the field name in first line, set few fields such as Vendor.FIELDCAPTION("No.") in SourceExpr of dataport field
(2) to export all the data, same fields were defined as (1)

It's supposed to export the file with header and data(starts from line 2)
But after running the dataport, there is always a blank line in line 2(nothing in this line), and vendor data starts in line 3

If I remove (1) the vendor starts in line 1 so I guess the problem comes from (1).
(Cause user needs to revised data it's needed to put the field name as header)

What's the extra blank line come from? ](*,)
Is there anybody knows about this kind of problem?
I will be appreciated for any comments.

Robin