BYD Co, the Chinese carmaker backed by Warren Buffett, fell the most in almost two years in Hong Kong trading after third-quarter profit dropped 99 per cent amid faltering sales. The shares declined 10 per cent to close at HK$51.05, the biggest drop since November 2008, after BYD posted net income of 11.34 million yuan ($1.7 million) for the three months ended September 30. It was the second-biggest decline among 982 stocks in the MSCI Asia Pacific Index.