Averaging Function

Hello,

I hope someone can help me with generating a production report average.

I have defined a table with the fields "Date", "Name of operator", "Pieces produced" and "Hours worked in shift".
Id like to know the average number of pieces produced per hour by each operator over the last 30 days.

I created a Summary view telling me the total pieces produced and total hours worked for each operator with a date filter for the last 30days. Id like the summary view to have an additional field where I can divide the "total pieces produced" by the "total hours worked" to give me the average. Is this possible???

I had previously created a hidden column in my source table where I divide the "Pieces produced" by the "hours in the shift" to give me an average pieces produced per hour for each row. And in the summary table, I average these results out. But I realize that this isn't a true average as it weighs all my rows the same...

Please help.