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.
A person with proven competence in this area CAN become "notorious" for developing spreadsheet applications, which eliminate drudgery from the process of using MS Excel to handle large amounts of data. Typically, work that takes hours or days will suddenly take minutes or seconds to finish.
One Possible Application: Plotting a pie chart based on income contributions from all your products and services(daily, weekly or monthly), and reviewing the automatically computed percentages/visual pie slices, can give very illuminating insight.
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.