You cannot due blanket math for purposes of the 940, and you should ignore the 941, the Social Security and Medicare, entirely for purposes of the 940. I taught payroll for years. Let's review 940:

The Feds offer Unemployment but they let the State run it. That means FUTA and SUI are intertwined.

The Feds only assess this tax up to the first $7,000 per employee gross wage. Think of that as an Admin function. The States take over from there. The reason you cannot do blanket math is that people come and go through the year, and each time a person is a new hire, they start over on the $7,000 limit.

Any time a person reaches the limit, their wages are still reported, but there is no further assessment.

It is not even assessed unless the person meets specific requirements:

https://www.irs.gov/taxtopics/tc759

The rate is not the same for all employers or all employees, as it hits the ground. It starts at 6.0%. If, for a specific employee, there is no State assessment or offset, it stays at 6.0%. For those employees who also are subject to SUI, the FUTA rate is typically credited back 5.4%, taking the FUTA rate to .6%. That means the typical annual max is $42 per employee, assuming their wages hit $7k and the employer is not in a credit reduction State, etc.

Someone would have been making payments and reporting to the Feds. You would use these amounts for determining the Employer Expense of this payroll provision.

I hope that helps.

You need to find a Payroll Professional to mentor you.