Mining equipment maker Joy Global Inc , which gets more than half of its revenue from coal miners, reported a 25 percent fall in quarterly net sales as customers continued to cut spending amid a slump in commodity prices. The company reported a net loss of $40.2 million, or 41 cents per share, in the first quarter ended Jan. 29, compared with a profit of $30.5 million, or 31 cents per share, a year earlier.