Calculating MLB payroll threshold for Luxury Tax

My google-fu has failed me.
It is the teams total salary averaging the cost of Contracts & Bonuses plus some number of benefits I cannot determine from googling.

It is the last part I am trying to determine.

Here is some of what I found:
2017 threshold: $195 million
2018: $197 million
2019: $206 million
These are the penalties:
• First time over: 20 percent tax on the overage
• Second time: 30 percent
• Third time: 50 percent
There are also surtaxes:
• Between $20 million and $40 million over the threshold: 12 percent
• $40 million over: 42.5 percent
• Second time $40 million over: 45 percent

Minimum salary: The Major League minimum salary will increase from $507,500 in 2016 to: $535,000 in 2017; $545,000 in 2018; $555,000 in 2019; and be subject to a cost-of-living adjustment in 2020 and 2021.

**Length of time on the DL: **The minimum time on the league’s disabled list will go from 15 days to 10.

Anyone know what the calculation is?

Sorry, I’m not clear. What is it you are looking for?
If it is total team salary than you can just google that.
If it’s for how that’s determined than most of what you’ve described is irrelevant, it’s dependent on the contracts for the individual players.
And I’m not sure how the DL stay fits into it at all.

From Philly Inquirer: “Payrolls are for 40-man rosters and include averages of multiyear contracts; health and pension benefits; clubs medical costs; insurance; workman’s compensation, payroll, unemployment and Social Security taxes; spring training allowances; meal and tip money; All-Star game expenses; travel and moving expenses; postseason pay; and college scholarships.”

In 2012: “A baseball source said the annual expense for medical benefits typically runs between $10 and $11 million per season. We’ll split it down the middle for our purposes and say $10.5 million.”

I’ve seen more recent estimates of $13 million average now.