The loading and unloading rate per hour, the handling capacity, and the average number of containers per ship handled in the terminals loaded high in the second component, which can be referred to as the productivity of the terminal.
Finally, the average port stay of the ships was found as a single variable loaded on the third component.
The original, unrotated principal components solution maximises the sum of squared factors loadings, efficiently creating the set of factors in the table above. However, unrotated solutions are hard to interpret because variables tend to load on multiple factors. Using the Varimax rotation realises an orthogonal rotation of the factor axes to maximise the variance of the squared factor loadings of a factor on all the variables (Table 7).