2000/01/01 Multiple commodities
    A  $5.00
    A  32 F
    B  $-12
    C

2000/01/02 Assertions
    A  $1  = $6
    A  1 F = 33 F
    A  $1  = $7
    A  1 F = 34 F
    B  3 F = 3 F
    B  $12 = $0
    B  1 F = 4 F
    C

2000/01/03 Assignments
    A       = $0
    A  -4 F = 30 F
    B  $-7  = $-7
    B       = 0 F
    C  $14
    C  8 F

test bal
                30 F  A
              $-7.00  B
               $7.00
               -30 F  C
--------------------
                   0
end test