Actually that was the defaults for an Avalon, so blame the page. In any case, if you want a return in terms of BTC you should be running it against what 100 BTC can buy today, meaning the cost of a 4-unit should be priced in dollar terms as just over $9k. Some calcs make this easier by allowing you to price cost in BTC too, but Coinish is down right now.
There's your figures for an Avalon 4-unit, even worse:
http://i.imgur.com/AyeMFLw.pngYour numbers are still a little mixed up.
3 module avalon hashes between 72 and 84 mh/s and originally cost roughly 75 btc.
4 module avalon hashes between 96 and 112 mh/s and originally cost roughly 100 btc.
