Here are 10 mistakes many people make to shortchange their retirement:

1. Setting money aside for college ahead of retirement: Many people decide that placing money into their children's college funds is more important than placing it into their own retirement fund. This is rarely a good idea. While it is possible to get loans for college, the same can't be said about retirement. Make sure that you contribute to your retirement fund first, and then work on providing some help for your children's college education.

2. Believing it's OK to wait: The magic of compounding interest is an important factor in growing your retirement fund. Even when you save small amounts in your early work history, the returns earned on that money will build on the base and, over time, will likely help you come out much further ahead than if you wait until later in life to begin your retirement savings. You should begin contributing to your retirement fund as soon as you begin your first job out of college (if not sooner). This will make the question of whether you're contributing enough to your retirement fund a non-issue in later years.

3. Not taking advantage of 401(k) matches: If your company provides matching funds for your 401(k) contributions, then not contributing -- or undercontributing -- is the same as throwing away free money. You should be taking full advantage of these matches from Day 1. Even when money is tight in your first years in the workforce, contributing up to the amount matched by your company in your 401(k) plan should be a top priority in your budget.

4. Accumulating credit card debt: Credit card debt means that you are paying interest to the credit card companies instead of growing a retirement fund. It's one of the worst things that you can do. When you end up paying credit card debt rather than placing the same amount of money into your 401(k) or IRA, your retirement fund will look a lot less healthy in the long run.

5. Counting on an inheritance: Counting on an inheritance or some other type of cash windfall for your retirement is playing with fire. While your parents may have a good retirement fund for themselves, there are so many things that can happen to quickly drain that fund. This is especially true if they get sick and have a lot of medical bills or if they need to go into long-term care. You should always remember that their money is theirs and not yours, and they are free to spend it any way that they like. If you do receive an inheritance, it should be looked at as an added bonus. But you should not count on it for your retirement fund.

6. Buying more house than you can afford: Purchasing a bigger house than you can afford can do huge damage to your retirement fund. This is because you're placing all your money into your mortgage instead of investing a portion of it for retirement. While a house does have some tax advantages on the mortgage loan, they are not nearly as good as the tax advantages of a 401(k) plan or an IRA. It's also much more difficult to get your retirement money out of the house than from a retirement fund. While housing as an investment is something you might want to consider to create more wealth, your own house should not be viewed as a retirement investment, and you should make sure that you can pay your mortgage and contribute to your retirement fund at the same time.

7. Neglecting insurance: Insurance exists for a reason: to protect you against an unlikely but high-cost event such as a fire, an unexpected serious illness, a natural disaster or a major auto accident. People who forgo insurance in an attempt to save money run the risk of putting their entire retirement savings in jeopardy if an unfortunate event takes place in their lives. You want to make sure that you are adequately insured to prevent this from happening.

8. Failing to take advantage of IRAs: You should be taking advantage of IRAs from the day that you are able to. If you fail to do so, it can be a huge blow to your retirement savings, since there is a limited amount that can be invested each year. IRAs are set up specifically so that you can maximize the amount that you have when you retire, and if you forgo them in your early years, you will do great damage to the amount available in your retirement fund when you get older.

9. Investing too conservatively: Investing too conservatively in your retirement fund means that you will not grow it adequately to meet your needs when you retire. You need to take into account that over time, inflation will take part of the purchasing power away from your retirement fund. As you get closer to retirement, you can make your investments more conservative, but in the early years you want to make sure that you are not investing too conservatively to yield the gains you need for retirement.

10. Investing too aggressively: While you don't want to invest too conservatively, you also don't want to be investing in things that promise huge returns but are extremely risky. You should determine a set amount of money each month to put into something like a stock index fund for your retirement. If you can spare more money after you have contributed to the retirement fund, it is acceptable to invest in something a bit more risky. However, you don't want to be risking the main portion of your retirement money in risky investments that could very well leave you with no money in the end.

By keeping these retirement fund pitfalls in mind, you can help ensure that you have plenty in your retirement fund when the time comes.

The S&P/Case-Shiller national home price index revealed that in 13 of 20 metro areas surveyed, home prices fell an average of 1.4 percent in the 12 months ended March 31, with half of that decline, 0.7 percent, coming in the first quarter.

The national index sank over a 12-month period for only the second time in its history and the first time since 1991. The drop is in stark contrast to a year ago, when home prices jumped 11.5 percent over the prior 12 months, according to the index.

Investors seem to believe the downturn will continue. The Chicago Mercantile Exchange trades contracts based on the Case-Shiller indexes that enable investors to bet on future housing price trends.

This product is fairly new with trading started about a year ago and is thinly traded. It also tilts a bit negatively because more traders seem to be using it as a hedge against falling home prices than as an investment.

Still, the futures trading has been reasonably accurate in predicting price changes (they've been down all year) and the latest trading reveals that investors are betting prices will continue to decline. The 10-city futures average has prices falling 3.9 percent in the 12 months through February 2008.

The Case-Shiller numbers, long considered the most accurate for gauging the direction and strength of housing prices, are based on prices compiled by the Office of Federal Housing Enterprise Oversight (OFHEO) and compare sales and mortgage refinancings for the same homes.

Among the 20 cities surveyed, Detroit took the biggest hit, with prices sliding 8.4 percent over the past 12 months. Michigan's economy has suffered from decades of cuts in domestic automobile manufacturing, and taken another hit from the recent spike in gas prices.

The second worst performer, San Diego, where prices fell 6.0 percent, was a bit more of a surprise; that California market has many things going for it, such as job growth, a growing population and little dependence on old, rust-belt industries.

Phoenix and Las Vegas experienced the steepest reversals of fortune from extremely hot to very cool. Prices in Phoenix were growing at a 49.3 percent annual rate in September 2005 while Las Vegas prices were soaring at a 53.2 percent rate in September 2004. But prices fell 3.0 percent and 1.6 percent in the latest 12 months, respectively.

But prices in San Diego, as in many California cities, had risen so quickly and reached so high a level (the median price in San Diego topped out above $600,000 last year) that the run-up became unsustainable. Prices had exceeded affordability for the average resident there.

A few cities bucked the trend. Seattle prices have grown 10 percent over the past 12 months, although the lion's share of that growth occurred earlier last year. But prices rose just 0.5 percent in the first quarter compared with the fourth quarter.

Other cities showing year-over-year increases were Charlotte (7.4 percent, but down 0.1 percent quarter-to-quarter), Portland, Oregon (7.0 percent and up just 0.1 percent quarterly) and Chicago (1.3 percent and flat quarterly).

The Case-Shiller news came on the heels of other negative numbers for housing in the past week. On Friday, the National Association of Realtors, reported that the pace of existing home sales fell to a four-year low in April.

A Thursday report from the Commerce Department showed a big jump in the pace of sales of new homes but that rise was driven by huge price discounts; the median price of a new home had dropped 11 percent compared with a year earlier.