UPDATE 2-Norfolk Southern profit falls short, stock drops

* Q1 EPS 47 cents vs 76 cents year ago

* Falls short of Street consensus of 56 cents per share

* NS says aggressively cutting costs

* Shares down 9 pct in after-market trade (Adds details of results, analyst estimates, updates stock action)

CHICAGO, April 21 (Reuters) - Norfolk Southern Corp (NSC.N) reported a worse-than-expected quarterly net profit on Tuesday, citing a 20 percent decline in freight volumes because of the recession, sending shares of the No. 4 U.S. railroad down 9 percent in extended trading.

The Norfolk, Virginia-based company reported first-quarter net income of $177 million or 47 cents per share, compared with $291 million or 76 cents a share, a year earlier.

Wall Street analysts had on average expected earnings per share for the quarter of 56 cents, according to Reuters Estimates.

Norfolk Southern's revenue for the quarter fell to $1.94 billion from $2.50 billion. Analysts had expected revenue of $2.03 billion.

The railroad said it was aggressively cutting costs in order to offset the drop in freight volumes.