The graph below shows the relative volumes of the cut on the coast, the southern interior, and the norther interior of BC. It also shows the allowable annual cut set by the chief forester, and the mid-term harvest level, both of which are established by periodical timber supply reviews. 2020 marked the first year during this period when the actual cut was lower than the mid-term harvest level. The mid-term harvest level is the level of cut that would be theoretically volumetrically sustainable—based on the ministry of forests computer modelling of forest growth and yield—out to about 50 years from current date. The ministry's estimate of this level is questionable for a number of reasons.