JOHANNESBURG (Reuters) - Namibia's central bank left its key lending rate unchanged at 6 percent, saying that while the decision was supportive of the economy it remained concerned about high household credit. "Household growth continues to finance largely unproductive imported luxury goods, which put additional pressure on the international reserves of the country," the Bank of Namibia said in a statement on Friday. It was the bank's second consecutive decision this year to leave rates unchanged.