Comment 22 for bug 511193

I do manufacture, and regularly order by the ton and produce by the mg and track by the microgram.

anyone that is doing composition of raw materials i.e. chemicals, food stuffs etc needs a large range (even than 10^9);

The reasons for this are simple:

I procure materials by the metric tonne
I schedule material use by the kg
I pack material by the gm
Said material has characteristics measured in mgs
Said material has quality assurance checks that test trace materials measured in mcg's

If you're going to fix this problem (and lord, I certainly consider it critical!) then you should do so in such a manner as to remove the problems with precisions period. Picking another range (other than 10^5) doesn't correct the problem, it is simply a palliative that will inevitably need corrections yet again. Email me at <email address hidden> if you want to discuss this further.

Additionally (since I'm just getting started with OpenERP and haven't located a mailing list yet), another point:
I'm not sure what rounding algorithm you are using but you should check out Bankers Rounding. Eliminates an inherent bias in rounding.