Sit back and relax from S&P 500 index fund investment

Stock market goes up and down all the time. Is there a low risk investment in the stock market? If you are lazy to research on the company annual reports, but still want to make a profit from the stock market, there may have a easy way.

S&P 500 is a stock market index containing the stocks of 500 large capitalization corporations, mostly US companies. There are many index funds and exchanged-traded funds tracking the performance of the S&P 500, e.g. BARCLAYS's iShares S&P 500 Index Fund. If you look at the index trend below, you can see that the S&P 500 is always in the uptrend for the long run (e.g. 30 years). This is mostly caused by the inflation.

If we buy the index on 1978 (30 years ago) and sell it now, what will be our return like?

Year 1978 June, index ~ 100
Year 2008 June, index ~ 1400

Using the calculation from the financial calculator, the compound return is closed to 9%. Not a very bad investment consider that you just need to buy once and forget about it :)