Rather than making Excel difficult because of a function that you only use once (I think that's something that Excel instructors or Excel VBA developers who earn money only with Excel should study), I think that the shortcut to conquering Excel is to continuously master the minimum content by repeating it and using it unconsciously. I think that Professor Kim Kyung-ja's lectures are more efficient because they focus on what you absolutely need to know rather than teaching you many functions. Thanks to you, I learned a lot about Excel. Thank you. ^^