Some documentation is already there on internal representation of numbers in ledger. It stores numbers as rational numbers avoid rounding problems arising of floating point representation.

The only time when rounding occurs is while displaying. But there are some other rounding problems in accountancy and it will be good to have a discussion on them.

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@@ -39,4 +39,4 @@ If rounding up was done per transaction, then the error per transaction may add

In the above example if there is rounding up in each transaction then the overall result will be off by few cents.

This problem does not occur in ledger as rounding is deffered till the last point that is at the time of display.