Contribution Method

The contribution method is similar to how the existing Attribution Group field calculates returns above the security level. The contributions and weights are aggregated at each level, and the return is calculated at each level from the sum of the contributions at each level divided by the sum of the weights at each level. This method requires that you commit security level investment base and returns for each single period. The investment base is converted to a weight, then the contribution is calculated as the weight multiplied by the return.

If committing monthly single period returns, you should commit the ABAL field for the investment base and Modified Dietz field for the return. If you are committing daily single period returns, a Detail Calculation field with the formula (BMV + Inflows) should be committed as the investment base and a Detail Calculation field with the formula ( ( (EMV + Outflows) / (BMV + Inflows) ) -1 ) * 100 should be committed as the return.