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Multiplication of a Rollup gives the wrong number [solved]

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I use this base for creating invoices, and my formulas are not calculating the right numbers, giving me incorrect sums.

GW correctly rolls up (using SUM(values)) hours from a separate table, and the field is formatted as a numeric with two decimal places. But when those sums are multiplied by the Rate (a Currency field with two decimal places), it gives the wrong number.

When I copy and paste the rollup values into a new column (GW2) that is just numbers rather than rollups, and then multiply by the rate, it gives the correct number.

Example: In the below screenshot, the total number of GW hours (“GW”) is 27.87, and the rate (“Rate”) is $35/hr. In reality, 27.87 * $35 = $975.45 (“Reality”), but the product given in “GW Subtotal” is $975.33.

46%20AM

Formulas used:
“GW” : SUM(values)
“GW Subtotal” : GWRate
“Reality” : {GW2}
{Rate}

This seems to be some bizarre rounding error, because some products are high and some are low.

Can you help?

Thanks,
Patrick

2 Replies 2

This is how calculations work in Excel too, you have trailing figures which are not being displayed. Try using ROUND(GW,2) to trim the excess penny fractions.

This fixed it. Thank you Tyler!