Home country bias occurs when investors concentrate their portfolios in shares and bonds from their home country. For example, while the UK stock market now represents only 3.2% per cent of the value of global equity markets (in 2006, it was 10.4%), British investors tend to allocate considerably more than this to UK stocks. It is a phenomenon that can often be detrimental to investment returns. Especially as the UK has lagged other world market in recent years.