PCT. of Pay

I‘d like to know when a company offers a driver a pct. for pay, what that really means?
Is it based upon the product value and you receive a pct. of what that is? OR
Is it a pct. of the freight charges being charged to the company and you receive a pct of that.
This was a job listing and I’m trying to figure how they are calculating the pay for this position.

Full time driver needed. Good Equipment, CDL CLASS A needed. Good Pay and small CO In business 29 plus years. So we are here to stay. Looking for the same.. Steady work. 2 or more years experience is required. Reefer experience preferred. You will need A CLEAN driving record. And A good work history. This in NOT a local job. Looking for A driver to run from South NJ to Binghamton NY Every night.. No, Pets. Fuel Cards and EZ Pass. and APU'S on all trucks. We are looking for long term drivers to grow with us.


Compensation: 28% PAY
This is 28% of what?

 

So the way I understand this it is a pct. of the freight charges being charged. The company that you drive for is offered a certain amount to do the job and you the driver then receives a pct of those freight charges.
Example:
Freight charges that are offered $1,000.
The company you work for then pays you a pct., such as 28% to make that run.
The driver gets paid, $280.00 to deliver this load.
I hope this is how I understand this is right.