Shares of TD Ameritrade ( AMTD) surged 6% in early trading Tuesday after the online broker posted record earnings for its fiscal first quarter On the heels of the merger between Ameritrade and TD Waterhouse's retail brokerage business one year ago, TD Ameritrade's profit rose 69% year over year, to $145.6 million, or 24 cents a share. Revenue nearly doubled from a year earlier and rose 9.5% from the previous quarter to $535.2 million. Analysts were predicting the brokerage would earn 22 cents a share on $517.4 million of revenue. TD Ameritrade's fiscal year ends on Sept. 30. TD Ameritrade's average client trades per day rose 52% from a year ago and 16% from the previous quarter, to 238,000. "After four record years, we've begun the new year with our best quarter ever," says CEO Joe Moglia. "We've delivered all of this while executing on the integration of TD Waterhouse and our client segmentation strategy." The company also reaffirmed that it anticipates per-share earnings for 2007 in "the midpoint of $1.10." TD Ameritrade now has client assets of $278.2 billion. Shares rose $1.01 to $18.36 in early trading.