We have just released a new commission schedule to further improve our real world trading simulation.

From now on, the commission for a trade will be calculated the following way: For trades below 1,000 shares, the commission will be $10 flat. For trades above 1,000 shares, the commission will be $10 + $0.01 for each share in excess of 1,000 shares. For example, a 1,500 share trade will incur a $15 commission (1,500 - 1,000) * $0.01 + $10 = $15.

This commission schedule is more realistic, as it makes high volume trades more expensive. In the real market, a large order would influence the stock price - this is now simulated on UpDown with a higher commission.