Changes

==== Example ====  

==== Example ====  

For a particular stakeholder group, at the end of Year 1 the count is 100 and at the end of Year 2 the count is 110. There are 10 new entrants in Year 2, so Cohort 1 is 100 and Cohort 2 is 10.  

For a particular stakeholder group, at the end of Year 1 the count is 100 and at the end of Year 2 the count is 110. There are 10 new entrants in Year 2, so Cohort 1 is 100 and Cohort 2 is 10.  

Imagine that the count drops to 99 at the end of Year 3. This would be a 10% reduction compared to the count at the end of the previous year (99/110 - 1). There are no new entrants in Year 3, so Cohort 3 = 0. Cohorts 1 and 2 are both multiplied by 0.9 (1 - 0.1), so Cohort 1 shrinks from 100 to 90 (100*0.9) and Cohort 2 shrinks from 10 to 9 (10*0.9). Combined, the sum of the reductions in Cohort 1 and Cohort 2 is 11 (10 + 1), which equals the reduction from 110 to 99 in the stakeholder count. More stakeholders left Cohort 1 than Cohort 2 because Cohort 1 is bigger. In Year 4, if the stakeholder count drops again, the new reduction would be applied to the remaining counts from Cohorts 1 and 2 (not their initial counts). In other words the reductions are applied cumulatively (i.e., they "stack").  

Imagine that the count drops to 99 at the end of Year 3. This would be a 10% reduction compared to the count at the end of the previous year (99/110 - 1). There are no new entrants in Year 3, so Cohort 3 = 0. Cohorts 1 and 2 are both multiplied by 0.9 (1 - 0.1), so Cohort 1 shrinks from 100 to 90 (100*0.9) and Cohort 2 shrinks from 10 to 9 (10*0.9). Combined, the sum of the reductions in Cohort 1 and Cohort 2 is 11 (10 + 1), which equals the reduction from 110 to 99 in the stakeholder count. More stakeholders left Cohort 1 than Cohort 2 because Cohort 1 is bigger. In Year 4, if the stakeholder count drops again, the new reduction would be applied to the ''remaining'' counts from Cohorts 1 and 2. In other words the reductions are applied cumulatively (i.e., they "stack").  

==== Technical explanation ====

==== Technical explanation ====

The RCC calculations keep track of how many stakeholders from each cohort are remaining in every period of the analysis, because the same cohort(s) may experience a reduction multiple times.   

The RCC calculations keep track of how many stakeholders from each cohort are remaining in every period of the analysis, because the same cohort(s) may experience a reduction multiple times.   

In every year in the analysis and for each cohort, a cohort weight is calculated. This weight is the product of all [1+(Percentage Change in Stakeholder Count)] values, after that cohort has entered the market. To reiterate, increases in the stakeholder count form new cohorts, so in these cases the percentage change for previous cohorts is 0. When the stakeholder count increases, the remaining counts from each cohort are simply multiplied by 1 (meaning they stay the same size).  

In every year in the analysis and for each cohort, a cohort weight is calculated. This weight is the product of all [1+(Percentage Change in Stakeholder Count)] values, after that cohort has entered the market. To reiterate, increases in the stakeholder count form new cohorts, so in these cases the percentage change is automatically set to 0. When the stakeholder count increases, the remaining counts from each cohort are simply multiplied by 1 (meaning they stay the same size).  

In Excel, these cohort weights are calculated using the PRODUCT function. For example, the number of Existing Stakeholders at the end of Year 4 could look like this: (Initial Count at Registration)*PRODUCT(1, 1, 0.9, 0.8). In successive years in the analysis, more [1+(Percentage Change in Stakeholder Count)] terms are included in the PRODUCT function. This ensures that successive reductions are applied cumulatively. As more values are added into the PRODUCT function, the cohort weight will either stay the same as it was in the previous year, or it will shrink. If there is an increase in the stakeholder count, then a new value of 1 is added to PRODUCT, which does not change the result compared to the previous year. Importantly, this means that any prior reductions are carried forward; e.g., PRODUCT(1, 0.9, 1). If there is a decrease in the stakeholder count, then a new value less than 1 is added to the product, which shrinks each affected cohort relative to its count in the previous year.  

In Excel, these cohort weights are calculated using the PRODUCT function. For example, the number of Existing Stakeholders at the end of Year 4 could look like this: (Initial Count at Registration)*PRODUCT(1, 1, 0.9, 0.8). In successive years in the analysis, more [1+(Percentage Change in Stakeholder Count)] terms are included in the PRODUCT function. This ensures that successive reductions are applied cumulatively. As more values are added into the PRODUCT function, the cohort weight will either stay the same as it was in the previous year, or it will shrink. If there is an increase in the stakeholder count, then a new value of 1 is added to PRODUCT, which does not change the result compared to the previous year. Importantly, this means that any prior reductions are carried forward; e.g., PRODUCT(1, 0.9, 1). If there is a decrease in the stakeholder count, then a new value less than 1 is added to the product, which shrinks each affected cohort relative to its count in the previous year.