I have the SMA First Nutrition stuff and going by baby boys age (2 weeks) he should have been getting 2oz but by his weight (9lbs 7oz) he should have been getting 4oz - I checked with HV and she said always make th eformula up to the weight on the chart, that way if they don't finish it you can dump the last oz or so but you're not leaving them hungry or having to top up with breastfeeding if the recommended oz for his age isn't enough (if that makes sense??). He is now a month old and was 11lbs 12.5oz so we have increased him to 5oz and more often than not he leaves about 1/2 oz or so. x
According to Similacs website a baby that age should eat 2-4oz every 2-3 hours.
4 oz is perfect. Careful to burp in between ounces or their little tiny tummies will hurt very badly. : )
It differs based on your baby. Mine is only two weeks old and she can down a 4 - 5 oz bottle every two hours, if not more.