The savings _ from using your "in house" expertise _ in terms of money and man_hours alone, will quickly justify the investment you make in "developing the needed skills" _ especially, when you compare what you spend with the cost of purchasing a commercial software application _ or even engaging the services of an Excel VB developer.
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.
Another question I ask, in answering the "Why Excel VB?" question is : "Why re_invent the wheel? ". My experiences(and those of others who favour the use of Excel VB like I do), confirm that to organise, and analyse data for (financial/management) report generation and decision making, you will save hundreds of hours using already in_built, pre_programmed Excel functions compared to a situation where you used Visual Basic proper. All the functions needed to achieve the above purposes already exist in Excel, so that you don't have to write them all from scratch as would be the case if you were to use Visual Basic. 3.It works even when you lack "In House" expertise.
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.