Carry-over #

The final consideration in calculating target workload is the carry-over of teaching credit from previous years. It is very difficult given the quantisation of the PWS to end up with all staff at their target load each year, and indeed in some cases it is impossible (e.g. where a staff member has both a large buyout and several PhD students with credit from the previous year they can have an irreducible load that far outstrips their target). We therefore permit credit, both positive and negative, to be carried between years. This is added to the workload from the current year to make a final total, that is compared to the target workload based on buyout & average load.

However, not all credit is carried over. If a member of staff is within $\pm 30$ hours of their target then they are regarded to have met their target for the year and no credit is carried forward. Any credit (or debit) outside this window is reduced by 30 hours before carrying forward. The amount of credit/debit is also capped at 200 hours. Thus staff are incentivised to `use it or lose it’, as their credit will taper away if left unspent for a number of years.

As a final step all carry overs are adjusted by the same amount such that the sum of the carry overs is zero, that is such that no net credit/deficit is carried into the next year from the past year. THis is usually a relatively small correction. If the staff was the same from one year to the other (i.e. no one leaving with a credit or deficit) and there was no shrinkage as explained above this step would not be necessary.