Don't forget that software engineers in the states tend to work more hours. For instance it's unlikely you're getting more than ~32 hours / week out of a German software engineer on average, due to caps on working hours and paid days off.
That puts the upper limit below what is likely to be the average in the states. Obviously this doesn't translate perfectly into productivity, but it is something you may want to keep in mind as an employer.
Don't forget that software engineers in the states tend to work more hours. For instance it's unlikely you're getting more than ~32 hours / week out of a German software engineer on average, due to caps on working hours and paid days off.
That puts the upper limit below what is likely to be the average in the states. Obviously this doesn't translate perfectly into productivity, but it is something you may want to keep in mind as an employer.