On February 27 this year FTSE100 reached an all-time high of just over 10,910. The next day, Donald Trump went to war with Iran. Global stock markets fell, as did the British blue-chip index. As the soaring price of oil threatened another inflation shock, investors braced for disaster. It didn’t happen. The index of the largest companies has remained stable and performed very well over the last year.

On Twelfth MagpieWe urge investors not to look past the short-term ups and downs of stock market investing. Shares may be very variable in the brief term, but this is a miniature price to pay for excellent long-term results.

See how exchanges apply your money

Over the last decade, the average Stocks and Shares ISA has grown at an average rate of 9.64% per year, with dividends reinvested. According to the advice website, the average Cash ISA return is just 1.21% per year Selfless.

Here’s what this means in practice, with an initial investment of £20,000.

At this rate, the average Cash ISA would turn £20,000 into £64,868 over 30 years. Equity investors would receive £304,406, almost five times as much. Of course, nothing is guaranteed.

Many investors have recently focused on the US stock market, which has gained popularity thanks to enormous mega-companies. However, the FTSE 100 index is also performing well. It has increased by 19.1% in the last 12 months. It also provided investors with plenty of dividends, with a trailing yield of around 3.1%. This brings the trailing 12-month total return to 22.2%.

This would turn an investment of £20,000 a year ago, in July 2025, into a quite useful £24,440. But it’s only one year. The real benefits of investing in stocks come through magic over decades compound effect shares.

Check out this star blue chip!

On Twelfth MagpieWe prefer to buy individual shares of British companies rather than passively follow the FTSE index. It’s a bit riskier, but potentially much more rewarding over time. Sometimes the action becomes gangster. This is what happened to an infrastructure service provider Computer center (LSE:CCC). It is the best performing FTSE 100 company over the last 12 months, up a staggering 114%.

Computacenter helps enormous organizations manage hardware, software and networks in the cloud and has released a number of invigorating commercial updates. Profits are forecast to double this year as investment in AI infrastructure and data centers accelerates, particularly in the US. In June, the company was rewarded with promotion to the FTSE 100 index.

Both the stock and the order book are growing, but as always there is risk. Computacenter operates on low margins, and any slowdown in economic sentiment could impact revenues and profits. And if AI turns out to be a bubble, it could take a major hit.

The stock is a little costly after such a forceful run, with a price-to-earnings ratio of 27. But not that costly given the opportunity. I think it’s worth considering for investors who understand risk, as part of a balanced FTSE 100 portfolio and FTSE250 stocks aimed at building wealth in the long run.

Is it worth investing £5,000 in Computacenter Plc now?

If investing expert Mark Rogers and his team have stock advice, it can pay to listen. After all, Twelfth Magpie’s flagship Share Advisor newsletter, which it has run for almost a decade, provides thousands of paying members with the best share recommendations from across the UK and US markets.

Mark believes there are 6 standout stocks that investors should consider buying right now. Want to see if Computacenter Plc is on the list?

Harvey Jones does not hold any position in the companies mentioned.