We programmers are paid for the time we do at work, but side projects like this very often aren't taken into account for the things we are expected to do during the regular work week. That is it's own problem, but this happens to a lot of people. You are paid for doing "the big projects", but then someone asks you to do this little thing on the side that gets bigger and bigger, but it's taking away time and focus on the big projects. Your boss probably doesn't think the side thing is what your job is.

Then take ownership and communicate so that they know.

If there's a better way then suggest it, or at the very least document the time and effort spent on these reports. If they are that critical (which they usually are for decision making) then it shouldn't be an issue when planning future work.

I think I understand the situation you described.

I’m not sure how “global level” organisations are, but mostly you just can’t convince a typical layman CEO that something looks easy, is really not easy.

Then when you serve the “small request”, next he’s in doubt why adding a small feature could increase the complexity of your work by a few order of magnitude.

Maybe today, but its going to keep growing until you hear it groaning under the weight of features that have more and more risk, and generally an unknown amount because those Excel methods are getting creakier and creakier over time as you try to accomplish more with the same tools.

The problem isnt Excel or any useful tool, its the misapplication of the tool and seeing people driving that same road already extremely well traveled.

http://www.laputan.org/mud/