This site quotes from 2009, and I haven't had a little one in a long time, so I don't know if 24 ounces is the right amount per day for a baby. Hope this helps. (Just a note, prices have increased a lot since 2009, so you do need to factor that in)
(Costs below are based on approximately 24 ounces of formula consumption per day.)
Pre-Mixed Ready-to-Feed Formula - Cost Per Day - $6.00, Cost Per Month - $180, Cost Per Year - $2,160
Concentrate in Cans (Mix with Water) - Cost Per Day - $4.60, Cost Per Month - $138, Cost Per Year - $1,600
Powdered in Cans (Mix with Water) - Cost Per Day - $3.75, Cost Per Month - $112, Cost Per Year - $1,350
Read more at Suite101: Cost Comparison of Breastfeeding and Formula: How Much Money Can You Save By Nursing Versus Formula Feeding?
http://www.suite101.com/content/cost-comparison-of-breastfeeding-and-formula-a128286#ixzz12AusDd8R