For example, it is estimated that around 70% of earnings for FTSE100 companies come from overseas, which is of course one of the reasons why the recent strength in sterling has not been good news for the FTSE, as overseas earnings lose some of their value. Naturally the reverse largely applies also, but quite apart from this any number of FTSE100 have operations (and therefore profits) largely focused abroad – quite apart from the more obvious mining and oil stocks, think tobacco, HSBC, Prudential and so on. There is also the world of Exchange Traded Funds, or ETFs, which these days means that an investor can slice and dice investments in many ways, such as by index, by country, by sector or by region. This gives the additional benefit of being specifically exposed to a theme in which the investor believes, without necessarily having to drill down into individual stocks. And finally One small practical consideration is that for an investor wishing to invest in US shares, a form known as W-8 BEN needs to be completed once every three years. This is a US tax document which allows UK residents to invest and hold US stocks and shares free from withholding tax. Full performance can be found on the company or index summary page on the interactive investor website. Simply click on the company's or index name highlighted in the article.