The 80ᚼ Pareto principle is based on Pareto's theory that 80% of the results one gets in a particular endeavour will be mainly due to 20% of areas to which one has applied efforts. In business this principle has been found to be true. Your data, properly converted into appropriate performance indicators, will show you where your largest margins come from. You can then channel more time and effort in that direction.
Variable Costs Control/Reduction was a strategy that worked extremely well for the company. Most memorable for me as a brewer, was the manner in which huge monetary savings/profit gains were made by successfully implementing variable cost reduction initiatives. For instance, a brewing ingredient switch was made to a more readily available local alternative which was many times cheaper, resulting in phenomenal savings and progressively increasing profit earnings even though the price of beer produced was not raised. This practice was routinely applied across the brewing and packaging processes in line with a well thought out plan.
The visiting head of the technical function only needed to look at the most recently plotted point on the chart (relative to preceding ones) for a Key Performance Indicator like. Cost per Hectolitres brewed(One Hectolitre = 100 Litres), to know if the brewery had stayed within the approved upper limit of spend(plotted as a straight line target across the same period) or not. Discussions would then take place based on identified "Exceptions"(which could be "good" e.g. savings made or "bad" e.g. monetary loss due to materials over_used), and "Actions To Be Taken" to correct or maintain observed performances agreed upon.
The claims I make above are NOT exaggerated. They are in fact based on my personal experiences doing the foregoing (a). As an manager in the challenging, fast_paced manufacturing work environment of a corporate multinational (b). As a solutions developer for individuals and businesses who use MS Excel for their work.