Want to use arrow keys to filter for particular variables

I've got a big table (~100,000 rows) with a filtered column named "VarName" -- the name of the variable that my user wants to see (e.g., AnnualRevenue, NumStaff). There are about 500 different VarNames.
When the user filters on a particular VarName, the application already shows (1) a graph showing the values of the variable, sorted from low to high, (2) the name of the variable, and for both the smallest and largest value, (3) the company name and the value.
The problem is that it's very time-consuming and tedious for the user to manually set the filter each time.
I want her to be able to simply press arrow keys (<= and =>) to scroll to the next or previous VarNames, automatically setting the filter so that everything but the user's selected VarName is filtered out.
I vaguely suspect this will involved OOP in VBA, but don't have a clue how to do it.