You might help the head 12 of the bestseller "The Deadline"
in order to calculate the time of creation of the software product.
Here is a summary of the Chapter:
1. Size of each project.
2. Especially at first with the choice of units of measurement — if you later you have to work with real data, it's a start and abstract units.
3. Build complex metrics based on simple (those are easy to calculate in any software product).
4. Collect archival data to consider the labour productivity in the already completed projects.
5. Work on the calculation formulas of complex synthetic metrics as long as the results are not will most accurately reflect the attitude of the abstract units to the specified archive data in the scope of work.
6. Swipe through the entire archive database the trend line, which will show the expected amount of work in the form of ratio values of complex synthetic metrics.
7. Now for each new project will be sufficient to calculate the value of the synthetic metric and use it to determine the expected amount of work.
8. Don't forget the "noise" on the line performance and use it as an indicator in determining the allowable deviations from the overall trajectory.