A baseline is a reference point against which other things can be compared or measured. It is used to identify whether there has been a change over time.
A baseline measurement should reflect the starting point prior to the strategies being implemented. It should then be used for comparison purposes to determine whether there has been a change over time.
However, comparing against a single data point is not always a reliable method of identifying a change - while you may see a difference between the original measurement and a later observation, there is no way to understand whether this change is caused by your strategies or whether it simply represents natural fluctuations in the data being observed.
Observing historical trends in the data before your strategies are implemented will help you to identify whether a change has occurred.
Figure 2 looks at on-time lodgment behaviour over a three-year period. Note the general direction evident in the data.