There are three custom columns in the project. 'Maturity Level' is from the SAMM and is the maturity level of that activity according to the model. The values in this column should not be changed. 'Implementation %' is how complete that task is. The cells in this column should get updated to reflect the degree of completion of the task. 'Maturity Score' is a calculated field. It is the current level of maturity for a task based on the Maturity Level and the Implementation %. The formula is ((Maturity Level)*(Implementation%)/100.  The Maturity Score is zero if there is no implementation of the task. When a task is 100% complete its Maturity Score is equal to its Maturity Value. So a task with Maturity Level of 1 that is 50% done has a Maturity Score of 0.5.  A task with a Maturity Level of 3 that is 50% done has a Maturity Score of 1.5.  Each set of six tasks roll up to their summary task. Complete maturity is achieved when each summary task is equal to 3. e.g. Governance will be a 3 when Strategy+Metrics, Policy+Compliance and Education+Guidance are all 3s.   The entire project will be a 3 when Governance, Construction, Verification and Deployment are all 3s.
In order for the Maturity Score calculations for summary tasks to work, the Maturity Level of each summary task must be 3. The Maturity Score of the summary tasks is calculated with the same formula as each task. The Implementation % of each summary task will be the sum of the fractional contributions of its subtasks. When all subtasks are 100% implemented the summary task Maturity Score will be 3.