Excel vb project-best practice

I'm not a vb developer neither so familiar with excel. Anyway i have a project to be done using MS Excel (cannot use access).
System is to provide a ratio analysis(ans some other analysis) of companies where data from an annual report need to entered to the system. Then based on several reports data I can derive graphs and all other information.

My question
Now I can store data in a single sheet like using is as as a database. it'll be like

CompanyName     Year     Data1     Data2    Data3...
 

Here the CompanyName can be duplicated as many Years data can be entered. If I use this method Each time I derive company data, I have to search for the relevant rows in the worksheet and keep lots of data in an array as I read through those rows and produce the final result.

Or I can use separate worksheet for each company. Then I only have to search for the relevant sheet name and perform operations in that worksheet it self easily.

So what is the best way to do this?
Thanks

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