Should we plan for project internal reporting?

It depends on the size and complexity of the project. However as many activities last for several months or a year it is recommended to set up quarterly intervals for internal reporting. Work progress and use of resources are the most important parameters to monitor. Only in the case of  specific problems is details needed. Otherwise a report on:

• Person months used against plan
• Work progress against expected result e.g. % accomplished
• Other costs consumables, equipment and travels (approx.)
• Problems or risks
• Unexpected costs (not in budget)

If resources used and work progress match your project should be on track. If you have spent 75% of the person months and only done 50% of the work you must explain and take corrective actions. You will only need approx. sum for other costs. It is only if there are unexpected costs that you need to act.

Number of person months spent and other cost you will get fairly exact. Work progress is your best estimation. Consider risks, complexity of the remaining work and be realistic.