UPDATE 1-U.S. junk bond funds post 4th biggest week of outflows ever -Lipper

(Adds analyst quote, details on high yield, byline)

NEW YORK, Nov 16 (Reuters) - U.S. fund investors walloped high-yield funds with their biggest week of withdrawals since March, Lipper data showed on Thursday.

The "junk" bond mutual funds and exchange-traded funds posted $4.4 billion in net withdrawals during the week ended Nov. 15, the fourth largest weekly outflow on record dating to 1992.

A stew of concerns hurt high-yield markets during the week, but the extensive withdrawals signal that investor sentiment may have been chief among them.

The U.S.-listed, $11.6 billion SPDR Bloomberg Barclays High Yield Bond ETF has posted negative performance in 14 of the last 19 days. Over the last month it has delivered a total return of negative 0.57 percent, with its price declines cushioned by the yield it pays.

The ETF posted $947 million in withdrawals during the week, Lipper estimates.

Three high-yield bond deals have been pulled from the market in the space of a week in the face of investor push-back.

Bank of America Corp analysts said in a note on Nov. 10 that volatility in high-yield has been "driven primarily by a confluence of several meaningful and yet only loosely related events." Those include the collapse of the Sprint Corp and T-Mobile U.S. Inc merger, government challenges to the AT&T Inc and Time Warner Inc tie-up, a credit downgrade for Teva Pharmaceutical Industries Ltd and the potential for tax reform to be delayed.

The analysts also said the flatness of the yield curve has been hurting high yield, partly by diminishing the appeal of banks, which benefit from a steeper yield curve that allows them to borrow cheaply, lend at higher rates and profit from the difference.

Elevated high-yield outflows are somewhat concerning, said Pat Keon, a senior analyst for Thomson Reuters' Lipper research unit, citing what he called the absence of an obvious catalyst.

"I wouldn't expect anything like I saw," he said. (Reporting by Trevor Hunnicutt; Editing by Tom Brown)