Hope this explains better! The document is primarily for presentation & I
want to round totals.
I add numbers below subtotal I'm afraid so subtotal 1 = 30150+75400 etc
Only subtotals and grand totals will be visible on the final document, but
they do need to add up correctly

subtotal 1 105,600 round=100
30,150
75,400
subtotal 2 109,800 round=100
7,000
73,500
19,550
9,720
subtotal 3 1,400 round=100
1,420

Grand total 217,000 round=1000
216,800 actual (sub1+sub2+sub3)
200 balancing total added to subtotal 3

How can I add the balancing figure to a subtotal (apart from doing it
manually)