Over the years Function Points have been a most scientific method of measuring the size of business capability. The main reason is that function point is technology agnostic and counts the output directly from the point of view of business user. So at the end of day any gain in the served function point of an application means an increased business capability.
Typically delivering function points comes at cost of certain number of code, typically for example if you deliver one function point this may cost an organization some 70 odd lines of code and the associated cost of development and effort.
Most organization have some level of bench mark of the typical lines of code they produce to delivery one function point.