Micro economics
About half of all software projects are cancelled by users who change their minds, whether or not the software engineers would have succeeded.
Maintenance: Most (70% or more) software engineering effort over the total lifetime of a system goes into maintenance and upgrades.
Delivery: In the course of taking a large software project from conception to end user acceptance (and actual use) the cost of developing the software will typically range from 20-30% of the total. Other activities (documentation, Training infrastructure, Support infrastructure, Deployment and Network design, etc) account for the other 70-80%.
Commercial developers write 12,000 lines of code per year.
Government developers write 1,500 lines of code per year.
See also