With the official beginning of the presidential elections we are hearing both Democrats and Republicans claim that their record on running the economy is better than their opponents'. Why not let the data speak?

This week we are all going to become experts on what GDP is and how it is calculated. You also know how to obtain data from FRED. Here's my suggestion.

Look at the Obama years and measure the increase in real GDP (percent change). How well did Obama do? Clearly, the global economic context constrains what anyone can do. So it is a good idea to benchmark the growth in US GDP using other countries, such as Canada or major European or Asian countries. Take your pick and compare real GDP growth during that period in the US to the corresponding figure in the benchmark country that you choose. Geeky note: this is a simplified version of what econometricians call DiD (Difference-in-Difference) estimation.

Now do the same with the Trump years. Compare US GDP growth during this period to the corresponding value in your benchmark. Note: it is not allowed to change benchmark from one period to the other. Pick one and stick to it. Different people will make different benchmark choices and report on their results.

I also encourage people to redo what others have done to check that there are no mistakes. When you work with data it is very easy to make mistakes and corrections should always be welcome.