Happy Friday! Here are eight great things I read this week. 

Human resources
's (NASDAQ:FB) Mark Zuckerberg has a great rule of thumb for hiring people

I will only hire someone to work directly for me if I would work for that person. ... It's a pretty good test and I think this rule has served me well.

This is great news

Unemployment fell in every state and the nation's capital last year -- something that hadn't happened since 1984.

This chart, posted by Barry Rithotz, pretty well sums up the average investor's thought process:

Supply and demand
The largest buyers of stocks by far are corporations themselves:

Repurchases by U.S. companies averaged $46.1 billion a month in 2014, compared with $7.1 billion in ETF and fund inflows. Investors have pulled more than $10 billion out of equity funds in January and February and sent $38 billion to bonds -- even as companies announced $132.7 billion more in buybacks. February's total of $104.3 billion was the highest on record, according to TrimTabs Investment Research.

Cheap gas is helping Americans:

Americans spent less on gasoline in January than in any month since 2009, according to data released by the Bureau of Economic Analysis on Monday. That left them with billions of dollars more to spend on everything from restaurants to electronics.

In total, Americans spent 0.2 percent less in January than in December, before adjusting for inflation. Ordinarily, that would be bad news for the economy, which depends heavily on consumer spending. But in this case, the slowdown was more than explained by an 18 percent drop in spending at the pump; set that aside, and spending would have risen 0.3 percent. That rise was partly because of higher utilities spending in response to the cold weather. But it also reflected higher spending in discretionary categories such as restaurants, hotels and recreational spending, which suggests that consumers are spreading their gas savings across the economy. 

Mr. Money Mustache is a popular blog about saving in order to achieve financial freedom and retire young. Economist Tyler Cowen has a rebuttal:

From an individual point of view, my worry is that happiness may not go up much in this early retirement and in fact it may go down; people seem to enjoy working, which is good for their health and their social involvement. Perhaps Mr. Money Moustache derives a sense of purpose from spreading this gospel, but most people would end up bored and indeed frustrated if they retired at age thirty as he has (apparently) done.

From a social point of view, if everyone did this, productivity would collapse. Workers over the age of thirty make the world go round, and teach and pass down skills to others. When you retire involves an external cost or benefit, and retirement can come either too early or too late.

Knock-on effects
Presented without comment

Shares of South Korea's leading condom maker soared for a second day after the country's Constitutional Court decriminalized adultery in a ruling that ended a decades-old anti-cheating law.

Unidus Corp. was up 11 percent to 3,475 won at 12:55 p.m. Friday in Seoul. The stock rose 15 percent yesterday, leaving it up almost 30 percent since the ruling. Hyundai Pharmaceutical Co., a maker of morning-after pills, rose 10 percent yesterday to the highest in more than five years.

Here's the oldest known video of Warren Buffett talking stocks, back in 1962:

Have a good weekend.