ISO-NE Monthly Meter Adjustments (MMA) from the last 2 months of the last quarter and the 1st month of the current quarter are applied to the first month's generation data.
The table below shows which quarter MMA adjustments are applied:
| Generating Month | Month MMA Received from ISO | Quarter MMA Applied |
| January | June | Q1 |
| February | July | Q2 |
| March | August | Q2 |
| April | September | Q2 |
| May | October | Q3 |
| June | November | Q3 |
| July | December | Q3 |
| August | January | Q4 |
| September | February | Q4 |
| October | March | Q4 |
| November | April | Q1 |
| December | May | Q1 |