Market demands. Traditionally from December through to April, it is called the “slow season.” Because the retail market slows down after Christmas. However, from mid January through to early February there is an upsurge of cargo moving to beat the Chinese New Year deadline. This usually keeps rates high as there is always space problems for cargo getting on vessels. From May through to November is the “peak season” where there is a big demand for cargo movement, so the Carriers raise the rates during this period, with the GRI (general rate increase), and PSS (peak season surcharge).
Bunker Fuel costs. This is a floating surcharge that the Carrier’s can change when oil prices rise or fall.
Terminal costs. This is when the Carrier has increases in costs when Terminal costs rise due to congestion problems, etc. The Carriers can add in new surcharges which have happened in the past and eventually get absorbed into the “all in ” rate quoted.