E-commerce giant Amazon just made the top tier of the Fortune 500 for the first time. It also raised the price of its Prime service from $99 a year to $119, and many analysts are optimistic about the change. In a note to clients, Doug Anmuth of JPMorgan said, "We do not expect the company to get much push-back from consumers given the increasing value of the service." The stock has generally been increasing in value too, so if you had invested in Amazon early on, your investment would have paid off. Your initial outlay of $1,000 in 2008 would be worth more than $20,000 as of May 25, according to CNBC calculations, or over 20 times as much, including price appreciation and dividend gains reinvested. In the charts below, all data splits are adjusted and gain-loss figures do not include dividends, interest, distributions or fees except on cash accounts. The portfolio value represents current holdings and the comparison charts represent current and historical prices of individual benchmarks, stocks or exchange-traded funds.

While Amazon's stock has performed well, any individual stock can over- or under-perform and past returns do not predict future results. That's perhaps why Warren Buffett, chief executive officer of Berkshire Hathaway, opted not to invest in Amazon when he had the chance. At Berkshire Hathaway's annual meeting last May, the self-made billionaire said he didn't appreciate the value of tech stocks at first: "I was too dumb to realize. I did not think [Bezos] could succeed on the scale he has." Citing Amazon's massive success, Buffett went on to say he "really underestimated the brilliance" of Amazon's execution and called Bezos "the most remarkable business person of our age."