HSBC Holdings PLC (LSE:HSBA) shares dropped 4.5% on Wednesday, wiping £7.4 billion from the bank's market value, after quarterly results missed expectations due to heavy losses on its investment in China's Bank of Communications (BoCom). HSBC's reported pre-tax profit fell 29% year-on-year to $6.3 billion, missing forecasts by nearly $700 million. The shortfall was driven mainly by $2.1 billion of dilution and impairment losses related to BoCom, after HSBC did not take part in a government-backed equity raise and also booked a further impairment charge. Additional restructuring and disposal costs brought total "notable items" to $2.8 billion, Shore Capital noted. Excluding these exceptional charges, HSBC's underlying performance was robust, with pre-tax profit actually coming in 10% ahead of consensus estimates on stronger income from core businesses.