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CHICAGO, Oct 25 (Reuters) - Cummins Inc , which makes diesel engines and power generators, reported on Thursday that third-quarter profit rose but still missed estimates, sending its shares to their biggest one-day percentage decline in nine years.
Net profit increased to $184 million, or $1.84 a share, from $171 million, or $1.69 a share, a year earlier. But analysts, on average, were expecting $1.93, according to Reuters Estimates.
Bear Stearns analyst Peter Nesvold attributed the shortfall to smaller-than-expected margins in Cummins' components business.
The Columbus, Indiana-based company said earnings rose because of a strong performance by its engine and power generation businesses.
Net sales rose 20 percent to $3.37 billion.
Cummins shares fell as much as 21 percent to $105.61, before closing at $111.56 on the New York Stock Exchange, off $22.17, or 16.6 percent. (Reporting by James B. Kelleher and Ben Klayman in Chicago and Robert MacMillan in New York)