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# Multiplication of a Rollup gives the wrong number [solved]

Topic Labels: Formulas
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Did you mean:  5 - Automation Enthusiast

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. 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  6 - Interface Innovator

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.  5 - Automation Enthusiast

This fixed it. Thank you Tyler! 