Oil extends slide below $30 on oversupply, weak China data

By Meeyoung Cho SEOUL (Reuters) - Crude futures fell on Tuesday, dropping below $30 a barrel and extending the previous day's losses by more than 3 percent, as worries about oversupply by top producers combined with more signs of a Chinese economic slowdown to spook the market. China's rail freight volume, a key economic indicator, dropped 11.9 percent in 2015 from a year ago, compared with a decline of 3.9 percent in 2014, the National Development and Reform Commission said on Tuesday, adding t