Ameritrade (NASDAQ:AMTD), which raised expectations about its third quarter last month, reported earnings today. Following several years of ho-hum results thanks to a beaten-down market and apathetic customers, the discount brokerage's earnings and trading activity are finally seeing a rebound. Shares have already done so, rising from around $5 back in April to a recent high of $9.16.

The company earned $49.9 million, or $0.12 a share, for the period ended June 27. In the year-earlier quarter, it made just $5.8 million, or $0.03 a share. Net revenues were also stronger, coming in at $188.5 million, 88% higher than the prior quarter's net revenues of $100.3 million.

Ameritrade's average daily trading volume also showed renewed signs of life, up 33% sequentially to 154,294. Client assets climbed to $48 billion, with customers opening 93,000 new accounts.

Other discount brokers have also enjoyed a resurgence in trading activity that is translating directly into better earnings. Charles Schwab (NYSE:SCH), which is one of David Gardner's Motley Fool Stock Advisor recommendations, expects its second-quarter earnings to top expectations. E*Trade (NYSE:ET) recently raised its 2003 earnings outlook. Ameritrade did the same thing today, in its Q3 earnings release.

All three companies appear to be optimistic that the worst times are behind them, and shareholders who held on through the ugliness have been rewarded.

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