From the link below:
But now that we’ve crunched those numbers, I think it’s necessary to point out how ridiculous it is to compare Reagan and Obama’s presidencies in the first place. The first and most important factor that makes this comparison ridiculous is the drastically changing jobs environment- specifically, the disappearance of a vast majority of the U.S. manufacturing sector. To put it more simply, about half of the manufacturing jobs that were available to unskilled workers (ie. those without a college degree) when Reagan became president had disappeared by the time Obama took office, most of them outsourced or replaced by machines and computers.
Here's an excellent analysis of what those comparisons are and why it is not helpful to keep making them:
(BTW, the stock market HAS done much better under "sochalist" President Obama than it did under President Reagan. But don't upset the you-know-who-folks with that fact. Presidents don't really have control over the stock market, but sometimes its growth is an indication of the confidence investors have -- sometimes.)