NEW YORK—The second quarter results of Ecolab Inc., a maker of cleaning and maintenance products for institutional use, barely changed from a year ago.

The company said net income was $48.19 million, or 37 cents a diluted share, compared with $48.41 million, or 36 cents a diluted share, in the second quarter of 2000. Sales rose 4% to $596 million.

After the earnings release, shares of the company fell 1.37% to $39.60 on the New York Stock Exchange.

Ecolab's stock, which has ranged from $33.25 to $45.6875 over the past year, underperformed the broader stock market in the first quarter, falling about 3.4% in the quarter compared with a 5.5% rise in the S&P-500.