I cull my closet regularly. I blame this on a chronic lack of hanging space rather than any innate thriftiness. The truth is, I’m the worst kind of thrifty impulse shopper. I scrounge through the racks of Goodwill and Buffalo Exchange, and justify each dubious "find" by its low-price tag…then find myself bagging and donating it as early as three months later.

Enough is enough. This coming New Year, one of my resolutions is to buy only what I love and will actually wear—versus choosing clothes (shoes, accessories, purses, etc.) by cost alone. So this easy cost-per-wear calculator will surely come in handy when the new year arrives!

A cost-per-wear formula 

The cost-per-wear (CPW) is a simple calculation.

  • Cost of the item / number of times it has been worn = cost-per-wear.

Here are two examples to help you learn to use the formula:

Example 1: I spent $88 on a pair of purple suede platform Miu Miu shoes (Buffalo Exchange, 2009). love these shoes—I wear them to practically every dressy occasion I get invited to!

  • $88/50 wears = $1.76 CPW = So totally worth it!

Example 2: I spent $25 on an ivory "ballerina" dress—a short cocktail affair my inner six year-old fell in love with. But it washes my skin tone out and I have no lingerie for it so I've worn it once (Buffalo Exchange, 2010).

  • $25/1 wear = $25 CPW = Whoops!

CPW'ing your current closet 

I've never thought about clothing, shoes and accessories as an investment—until now. But it makes perfect sense! TLC's "What Not to Wear" stylist Lindsey Weiner told LearnVest, "most of us only wear about 20% of the contents of our closet regularly…ideally, that number should be at least 50%."

Evaluating your current closet in terms of CPW is the first step to improving your sartorial investment skills.

Here's what to do:

  • Divide your closet into categories: shirts, blouses, suits, dresses, pants, etc. Pull out your "go to" items (Hint: if you are hesitant, it probably isn't a "go to" item). The items you pull out are your best apparel investments and you want to look for more like these in the future.
  • Now do the same with your accessories, shoes and outerwear.
  • Depending on how much you are left with, and what the remainder is worth (in dollars and cents as well as sentimental value) you can continue, focusing next on seasonal "go to" favorites—well-loved, well-used items you only wear when it’s really hot or cold.
  • When you’re finished with both rounds, what’s left is fair game for reselling, donating or a "closet swap" party with friends.

CPW'ing your future purchases 

Here, you will begin learning to balance impulse with practicality—want with need. Here are five tips to guide you:

1. Is the item versatile? Can it take you from playtime at the park with the kiddos to happy hour with adult friends—or a day at the office to a networking cocktail party? If so, you may be on to a good CPW item.

2. Is it classic? Trends come and go—and the right accessories with classic foundational pieces can keep you current without draining your bank account. In other words, if you don't see it going out of style anytime soon—or ever—its potential CPW will likely reward you for making the purchase.

3. Is it seasonal? What you want to avoid here is anything that is too light for one season and too heavy for the other. Jackets, sweaters, hats—these tend to be seasonal buys. Just make sure it really "fits" the season, and you can probably count on it delivering a good CPW over time.

4. Is it durable? The truth is, many wearables today start to show their age after just a few wearings. But if you can foresee the item keeping its good looks (with a bit of routine maintenance) for quite some time to come, the CPW likely justifies the buy.

5. Is it your "dream" item? In all this talk of CPW, don't forget about those few items that simply make your heart sing. If you love, love, love it, put it on the table. If you have been dreaming about it for years, it just might be time to act on that dream. So what if it’s not totally (or at all) practical! Here, if you truly love it, then you will find a way to work it into your wardrobe, and it will justify its presence in your closet over time.