Online broker Ameritrade ( AMTD - Get Report) said it averaged 133,000 client trades a day in May and opened 17,000 new accounts, both down from the previous month. As of May 27, qualified accounts totaled 1.73 million. The company closed 13,000 accounts during May, resulting in 3.7 million total accounts. In April, Ameritrade posted 140,000 average client trades a day and opened 34,000 new accounts. The company reported average client margin balances in May of about $3.4 billion. On May 27, client margin balances totaled $3.3 billion and client assets were $77.3 billion, of which cash and money market assets totaled $13.2 billion. Ameritrade has said it has held talks about a potential merger with TD Waterhouse USA, part of Toronto-Dominion Bank ( TD - Get Report). E*Trade ( ET - Get Report) has also expressed interested in joining up with Ameritrade and is reportedly now offering a 49.5% stake in the combined company along with $2 billion in cash.