Simple seasonalization question

I am having trouble interpreting Anapedia's Time Aggregation functionality which states that:

I have the following simple example with three modules:
Annual sales by product group and employee
Seasonal percentages by product group

Monthly sales by product group and employee

Module: Annual sales

Page:  Product group, Employee

Line item:  Annual sales

Columns: Time (Time scale has been set to Year; calendar type Calendar month/quarter/year used)

Module: SeasonalPercentages

Page:  Product group

Line item: SeasonalPercent

Columns: Time (Time scale has been set to month)

Module: MonthlySales

Pages:  Product group, Employee name

Line item:  Monthly sales

Columns: Time (Time scale has been set to month)

My question:  What is the correct formula for line item Monthly sales?

Recognizing that the employee does not affect sales seasonality, my first cut is as follows:

AnnualSales.Annual Sales * SeasonalPercentages.MonthlyPercent

An Excel spreadsheet with a visual example of this issue is attached.