Cycles oscillate around an axis, or center line. The axis is also known as the “inflection point” of the cycle. The amplitude (or magnitude) of the cycle is measured from the crest to the axis. Note that some analysts measure amplitude from crest to trough, rather than cred to axis. This is an important point, because if you’re looking at another analyst’s data, you must understand how they measure a cycle’s amplitude in order to properly use and interpret the data you’re looking at.
Amplitude is measured in units of price.
Once you know the period and amplitude of a given cycle, you can begin to extrapolate future iterations of the cycle into the future.