Adam Hayes, Ph.D., CFA, is a financial writer with 15+ years Wall Street experience as a derivatives trader. Besides his extensive derivative trading expertise, Adam is an expert in economics and ...

Calculating the mean is one of many methods of finding an average. To calculate the mean, you add up all the numbers in the set, then divide the total by the number of numbers you added.

Job B is gig work, where you might earn $7,500 one month and $2,000 the next. They have the same average but mean something very different when you are planning your rent or mortgage payments.

Countries where the US runs a trade surplus were also hit, facing a flat 10 per cent rate regardless, as did nations where trade was roughly even ...