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.
In addition, an Excel VB developer( who in many cases will tend to be a user turned developer, and is therefore likely to easily see things from your perspective) _ unlike a programmer _ is more likely to be positively disposed to working with you to ensure the application meets your practical needs. S/he will readily understand that the final application is meant to help solve a real problem(s), and will therefore build it to match those expectations.
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.
For instance if a company had five drink brands in the market but notices that Brand A, which has a profit margin of at least twice the others is in greatest demand, they could (a) focus production efforts on that brand, so that more bottles go out to trade (b) Apply Best Practice/Continuous Improvement initiatives that would result in lower costs of producing each bottle of Brand A so that even though the market price remains fixed, the company is able to earn increasing profit margins per bottle.