S&P ends flat as healthcare advance offset by lower oil

By Sinead Carew NEW YORK (Reuters) - The S&P 500 ended the day unchanged on Tuesday as lower oil prices hurt energy stocks, offsetting advances in healthcare and financial sectors, while the Nasdaq ended at another record high. The Dow's 20,000 milestone remained elusive as it was weighed down by declines in IBM , Merck & Co , Exxon Mobil and Procter & Gamble . Traders were holding fire ahead of the upcoming corporate earnings season and the Jan. 20 inauguration after which they expe