What's your time worth? $20 an hour? Maybe $100?

　　When it comes to finances, people usually know the value of their savings and investments. And, after checking Zillow three times a week, they have an idea of the value of their homes. But all too often, they haven't put a price on their time and labor.

　　They should. It's far more useful, and it can help you save a lot of money.

　　Over the past couple of decades, as stocks and home prices climbed to the sky, many of us got in the habit of paying others to do jobs that we once did ourselves. Sometimes it was sensible: In a booming economy, it can be smart to focus on making money and pay others to do the chores. But just as often people were simply lazy, happy to swap some money to save time.

　　Now the economy has lost a wheel. Millions of Americans are unemployed and underemployed. One way to boost our income is to take back many of the chores we outsourced to others.

　　Do the math.

　　If you make a sandwich at home instead of buying one at work, it may take you five minutes in the kitchen and save you $6.

　　Is it worth it? That depends on how you value your time. To pocket $6 from five minutes' work is the equivalent of earning $72 an hour. And the savings are free of tax.

　　That's a good wage. Yet judging by the local sandwich shops in any downtown area, lots of people would rather buy.

　　Should you sign up for a store credit card just to save 10% on your first day's purchases? It may take an hour -- including time on hold -- to get, pay off and eventually cancel the card. If you're spending $200, the savings may not be worth it. But if you're spending $1,000, they might be. Where's the cut-off point?

　　How about driving 20 minutes extra to get to the cheaper supermarket? If your time is worth $50 an hour after tax, you'll have to save about $17 to make it worth your while.

　　Clipping coupons is often associated with little old ladies buying cat food. But if 10 minutes' work saves $10 on groceries, that's $60 an hour after tax.

　　Should you take your family out for an $80 meal instead of making one at home? That depends on what your time is worth to you.

　　Obviously there is no magic number. The answer varies for everybody. But at least do the math. If you convert every potential opportunity into an hourly wage, it makes the trade-off clear. And of course money saved is tax-free.

　　The recession is doing funny things with the price of time.

　　Technically it's risen in value. Although hardly anyone seems to have noticed, the government's latest figures show that hourly wages in real terms -- which had pretty much stagnated for decades -- have just jumped to their highest levels since the 1970s. You can thank cheaper prices in the stores, as well as higher pay.

　　Yet time is actually getting less valuable.

　　People, after all, have more of it: One worker in six is either unemployed or underemployed, and those still in jobs are working fewer hours, according to the Bureau of Labor Statistics.

　　And most people value cash savings more, so they are more willing to spend a little extra time to save a few more dollars.

　　A world of Facebook, reality TV shows and endless business meetings hardly values time very highly. As Robin Williams once observed on Mork & Mindy, 'Earthlings kill time.'

　　The good news: Converting time to cash is one of the easiest ways to boost your savings. It helps to do the math.

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