this is not a bug, but a VFP feature by design

CLEAR 
CLOSE TABLES ALL

CREATE CURSOR table1 (id I, coeff1 I)
INSERT INTO table1 VALUES (0,32767)
INSERT INTO table1 VALUES (1,32767)

CREATE CURSOR TEST (fk I,n N(9,6))

FOR K=1 TO 4000
	INSERT INTO TEST VALUES (m.k%2,0.100000)
NEXT

SELECT	SUM(n*coeff1) VFP,'13106800,000000' Exact FROM test JOIN TABLE1 ON FK=ID

* of course ROUND() is useless
SELECT	ROUND(SUM(ROUND(ROUND(n,6)*ROUND(coeff1,6),6)),6) VFP,'13106800,000000' Exact FROM test JOIN TABLE1 ON FK=ID

this is a simple example, but it is possible to build a combination of numbers
what it produces smaller values but however wrong.

A workaround exists, but it is orrible